diff --git a/lib/base64.c b/lib/base64.c
index c9e8a382c..2302eb014 100644
--- a/lib/base64.c
+++ b/lib/base64.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -280,7 +280,7 @@ int main(int argc, char **argv, char **envp)
 
     for(j=0; j < 0x10; j++)
       if((j+i) < dataLen)
-        printf("%c", isgraph(data[i+j])?data[i+j]:'.');
+        printf("%c", ISGRAPH(data[i+j])?data[i+j]:'.');
       else
         break;
     puts("");
diff --git a/lib/escape.c b/lib/escape.c
index c569902f6..9552b0f31 100644
--- a/lib/escape.c
+++ b/lib/escape.c
@@ -116,10 +116,6 @@ char *curl_easy_escape(CURL *handle, const char *string, int inlength)
   return ns;
 }
 
-#define ishex(in) ((in >= 'a' && in <= 'f') || \
-                   (in >= 'A' && in <= 'F') || \
-                   (in >= '0' && in <= '9'))
-
 char *curl_easy_unescape(CURL *handle, const char *string, int length,
                          int *olen)
 {
@@ -138,7 +134,7 @@ char *curl_easy_unescape(CURL *handle, const char *string, int length,
 
   while(--alloc > 0) {
     in = *string;
-    if(('%' == in) && ishex(string[1]) && ishex(string[2])) {
+    if(('%' == in) && ISXDIGIT(string[1]) && ISXDIGIT(string[2])) {
       /* this is two hexadecimal digits following a '%' */
       char hexstr[3];
       char *ptr;
diff --git a/lib/ftp.c b/lib/ftp.c
index eb945ef0b..e3d14a2ba 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -252,8 +252,8 @@ static void ftp_respinit(struct connectdata *conn)
 }
 
 /* macro to check for the last line in an FTP server response */
-#define lastline(line) (isdigit((int)line[0]) && isdigit((int)line[1]) && \
-                        isdigit((int)line[2]) && (' ' == line[3]))
+#define lastline(line) (ISDIGIT(line[0]) && ISDIGIT(line[1]) && \
+                        ISDIGIT(line[2]) && (' ' == line[3]))
 
 static CURLcode ftp_readresp(curl_socket_t sockfd,
                              struct connectdata *conn,
@@ -2177,7 +2177,7 @@ static CURLcode ftp_state_get_resp(struct connectdata *conn,
           if('(' == *bytes)
             break;
           /* skip only digits */
-          if(!isdigit((int)*bytes)) {
+          if(!ISDIGIT(*bytes)) {
             bytes=NULL;
             break;
           }
@@ -3208,7 +3208,7 @@ static CURLcode ftp_range(struct connectdata *conn)
 
   if(data->reqdata.use_range && data->reqdata.range) {
     from=curlx_strtoofft(data->reqdata.range, &ptr, 0);
-    while(ptr && *ptr && (isspace((int)*ptr) || (*ptr=='-')))
+    while(ptr && *ptr && (ISSPACE(*ptr) || (*ptr=='-')))
       ptr++;
     to=curlx_strtoofft(ptr, &ptr2, 0);
     if(ptr == ptr2) {
diff --git a/lib/http.c b/lib/http.c
index 0b3111f47..e31730e7d 100644
--- a/lib/http.c
+++ b/lib/http.c
@@ -569,7 +569,7 @@ CURLcode Curl_http_input_auth(struct connectdata *conn,
   }
 
   /* pass all white spaces */
-  while(*start && isspace((int)*start))
+  while(*start && ISSPACE(*start))
     start++;
 
   /*
@@ -1051,7 +1051,7 @@ Curl_compareheader(char *headerline,    /* line to check */
   start = &headerline[hlen];
 
   /* pass all white spaces */
-  while(*start && isspace((int)*start))
+  while(*start && ISSPACE(*start))
     start++;
 
   /* find the end of the header line */
@@ -1558,7 +1558,7 @@ static CURLcode add_custom_headers(struct connectdata *conn,
       /* we require a colon for this to be a true header */
 
       ptr++; /* pass the colon */
-      while(*ptr && isspace((int)*ptr))
+      while(*ptr && ISSPACE(*ptr))
         ptr++;
 
       if(*ptr) {
@@ -1725,12 +1725,12 @@ CURLcode Curl_http(struct connectdata *conn, bool *done)
        redirected request is being out on thin ice. Except if the host name
        is the same as the first one! */
     char *start = ptr+strlen("Host:");
-    while(*start && isspace((int)*start ))
+    while(*start && ISSPACE(*start ))
       start++;
     ptr = start; /* start host-scanning here */
 
     /* scan through the string to find the end (space or colon) */
-    while(*ptr && !isspace((int)*ptr) && !(':'==*ptr))
+    while(*ptr && !ISSPACE(*ptr) && !(':'==*ptr))
       ptr++;
 
     if(ptr != start) {
diff --git a/lib/http_chunks.c b/lib/http_chunks.c
index 8e9947f5d..f398b100c 100644
--- a/lib/http_chunks.c
+++ b/lib/http_chunks.c
@@ -115,7 +115,7 @@ CHUNKcode Curl_httpchunk_read(struct connectdata *conn,
   while(length) {
     switch(ch->state) {
     case CHUNK_HEX:
-      if(isxdigit((int)*datap)) {
+      if(ISXDIGIT(*datap)) {
         if(ch->hexindex < MAXNUM_SIZE) {
           ch->hexbuffer[ch->hexindex] = *datap;
           datap++;
diff --git a/lib/http_digest.c b/lib/http_digest.c
index e1aec3919..8b605d5c5 100644
--- a/lib/http_digest.c
+++ b/lib/http_digest.c
@@ -75,7 +75,7 @@ CURLdigest Curl_input_digest(struct connectdata *conn,
   }
 
   /* skip initial whitespaces */
-  while(*header && isspace((int)*header))
+  while(*header && ISSPACE(*header))
     header++;
 
   if(checkprefix("Digest", header)) {
@@ -93,7 +93,7 @@ CURLdigest Curl_input_digest(struct connectdata *conn,
       char content[128];
       size_t totlen=0;
 
-      while(*header && isspace((int)*header))
+      while(*header && ISSPACE(*header))
         header++;
 
       /* how big can these strings be? */
diff --git a/lib/http_negotiate.c b/lib/http_negotiate.c
index 70062f85a..eb5bd92d1 100644
--- a/lib/http_negotiate.c
+++ b/lib/http_negotiate.c
@@ -124,7 +124,7 @@ int Curl_input_negotiate(struct connectdata *conn, char *header)
   bool gss;
   const char* protocol;
 
-  while(*header && isspace((int)*header))
+  while(*header && ISSPACE(*header))
     header++;
   if(checkprefix("GSS-Negotiate", header)) {
     protocol = "GSS-Negotiate";
@@ -160,7 +160,7 @@ int Curl_input_negotiate(struct connectdata *conn, char *header)
     return ret;
 
   header += strlen(neg_ctx->protocol);
-  while(*header && isspace((int)*header))
+  while(*header && ISSPACE(*header))
     header++;
 
   len = strlen(header);
diff --git a/lib/http_ntlm.c b/lib/http_ntlm.c
index 7444a400c..8205a8fea 100644
--- a/lib/http_ntlm.c
+++ b/lib/http_ntlm.c
@@ -218,13 +218,13 @@ CURLntlm Curl_input_ntlm(struct connectdata *conn,
   ntlm = proxy?&conn->proxyntlm:&conn->ntlm;
 
   /* skip initial whitespaces */
-  while(*header && isspace((int)*header))
+  while(*header && ISSPACE(*header))
     header++;
 
   if(checkprefix("NTLM", header)) {
     header += strlen("NTLM");
 
-    while(*header && isspace((int)*header))
+    while(*header && ISSPACE(*header))
       header++;
 
     if(*header) {
diff --git a/lib/mprintf.c b/lib/mprintf.c
index 543a39f15..610395318 100644
--- a/lib/mprintf.c
+++ b/lib/mprintf.c
@@ -171,7 +171,7 @@ int curl_msprintf(char *buffer, const char *format, ...);
 static long dprintf_DollarString(char *input, char **end)
 {
   int number=0;
-  while(isdigit((int)*input)) {
+  while(ISDIGIT(*input)) {
     number *= 10;
     number += *input-'0';
     input++;
diff --git a/lib/parsedate.c b/lib/parsedate.c
index 37b4ddfe3..0bb6d0c5a 100644
--- a/lib/parsedate.c
+++ b/lib/parsedate.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -213,7 +213,7 @@ static int checktz(char *check)
 static void skip(const char **date)
 {
   /* skip everything that aren't letters or digits */
-  while(**date && !isalnum((int)**date))
+  while(**date && !ISALNUM(**date))
     (*date)++;
 }
 
@@ -256,7 +256,7 @@ static time_t Curl_parsedate(const char *date)
 
     skip(&date);
 
-    if(isalpha((int)*date)) {
+    if(ISALPHA(*date)) {
       /* a name coming up */
       char buf[32]="";
       size_t len;
@@ -286,7 +286,7 @@ static time_t Curl_parsedate(const char *date)
 
       date += len;
     }
-    else if(isdigit((int)*date)) {
+    else if(ISDIGIT(*date)) {
       /* a digit */
       int val;
       char *end;
diff --git a/lib/setup.h b/lib/setup.h
index a02834ecd..4f1a3c1cd 100644
--- a/lib/setup.h
+++ b/lib/setup.h
@@ -348,6 +348,16 @@ int fileno( FILE *stream);
 #define DEBUGF(x)
 #endif
 
+#ifndef ISSPACE
+/* typecasting craze to avoid negative number inputs to these macros */
+#define ISSPACE(x) (isspace((int)((unsigned char)x)))
+#define ISDIGIT(x) (isdigit((int)((unsigned char)x)))
+#define ISALNUM(x) (isalnum((int)((unsigned char)x)))
+#define ISXDIGIT(x) (isxdigit((int)((unsigned char)x)))
+#define ISGRAPH(x) (isgraph((int)((unsigned char)x)))
+#define ISALPHA(x) (isalpha((int)((unsigned char)x)))
+#endif
+
 /*
  * Include macros and defines that should only be processed once.
  */
diff --git a/lib/strtoofft.c b/lib/strtoofft.c
index b11755b1b..3ab1bfdff 100644
--- a/lib/strtoofft.c
+++ b/lib/strtoofft.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -55,7 +55,7 @@ curlx_strtoll(const char *nptr, char **endptr, int base)
 
   /* Skip leading whitespace. */
   end = (char *)nptr;
-  while (isspace((int)end[0])) {
+  while (ISSPACE(end[0])) {
     end++;
   }
 
diff --git a/lib/transfer.c b/lib/transfer.c
index e2df5fc12..25645c97d 100644
--- a/lib/transfer.c
+++ b/lib/transfer.c
@@ -762,7 +762,7 @@ CURLcode Curl_readwrite(struct connectdata *conn,
 
               /* Find the first non-space letter */
               for(start=k->p+13;
-                  *start && isspace((int)*start);
+                  *start && ISSPACE(*start);
                   start++)
                 ;  /* empty loop */
 
@@ -772,7 +772,7 @@ CURLcode Curl_readwrite(struct connectdata *conn,
 
               if(end) {
                 /* skip all trailing space letters */
-                for(; isspace((int)*end) && (end > start); end--)
+                for(; ISSPACE(*end) && (end > start); end--)
                   ;  /* empty loop */
 
                 /* get length of the type */
@@ -877,7 +877,7 @@ CURLcode Curl_readwrite(struct connectdata *conn,
 
               /* Find the first non-space letter */
               for(start=k->p+17;
-                  *start && isspace((int)*start);
+                  *start && ISSPACE(*start);
                   start++)
                 ;  /* empty loop */
 
@@ -957,7 +957,7 @@ CURLcode Curl_readwrite(struct connectdata *conn,
 
                 /* Skip spaces and tabs. We do this to support multiple
                    white spaces after the "Location:" keyword. */
-                while(*start && isspace((int)*start ))
+                while(*start && ISSPACE(*start ))
                   start++;
 
                 /* Scan through the string from the end to find the last
@@ -966,7 +966,7 @@ CURLcode Curl_readwrite(struct connectdata *conn,
                    there. This logic strips off trailing whitespace, but keeps
                    any embedded whitespace. */
                 ptr = k->end_ptr-1;
-                while((ptr>=start) && isspace((int)*ptr))
+                while((ptr>=start) && ISSPACE(*ptr))
                   ptr--;
                 ptr++;
 
diff --git a/lib/url.c b/lib/url.c
index 312862dcb..d23660515 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -3252,7 +3252,7 @@ static CURLcode CreateConnection(struct SessionHandle *data,
     /* detect and extract RFC2732-style IPv6-addresses */
     if(*proxyptr == '[') {
       char *ptr = ++proxyptr; /* advance beyond the initial bracket */
-      while(*ptr && (isxdigit((int)*ptr) || (*ptr == ':')))
+      while(*ptr && (ISXDIGIT(*ptr) || (*ptr == ':')))
         ptr++;
       if(*ptr == ']') {
         /* yeps, it ended nicely with a bracket as well */
diff --git a/src/main.c b/src/main.c
index af3f4355f..24eec6b34 100644
--- a/src/main.c
+++ b/src/main.c
@@ -380,7 +380,7 @@ static void warnf(struct Configurable *config, const char *fmt, ...)
       if(len > (int)WARN_TEXTWIDTH) {
         int cut = WARN_TEXTWIDTH-1;
 
-        while(!isspace((int)ptr[cut]) && cut) {
+        while(!ISSPACE(ptr[cut]) && cut) {
           cut--;
         }
 
@@ -933,7 +933,7 @@ static int formparse(struct Configurable *config,
           while(ptr && (FORM_FILE_SEPARATOR!= *ptr)) {
 
             /* pass all white spaces */
-            while(isspace((int)*ptr))
+            while(ISSPACE(*ptr))
               ptr++;
 
             if(curlx_strnequal("type=", ptr, 5)) {
@@ -1155,7 +1155,7 @@ static void cleanarg(char *str)
 static int str2num(long *val, char *str)
 {
   int retcode = 0;
-  if(isdigit((int)*str))
+  if(ISDIGIT(*str))
     *val = atoi(str);
   else
     retcode = 1; /* badness */
@@ -1961,7 +1961,7 @@ static ParameterError getparameter(char *flag, /* f or -long-flag */
           if(ptr &&
              (ptr == &nextarg[1]) &&
              (nextarg[2] == '\\' || nextarg[2] == '/') &&
-             (isalpha((int)nextarg[0])) )
+             (ISALPHA(nextarg[0])) )
              /* colon in the second column, followed by a backslash, and the
                 first character is an alphabetic letter:
 
@@ -2463,7 +2463,7 @@ static int parseconfig(const char *filename,
     int lineno=0;
     bool alloced_param;
 
-#define isseparator(x) (((x)=='=') || ((x) == ':'))
+#define ISSEP(x) (((x)=='=') || ((x) == ':'))
 
     while (NULL != (aline = my_get_line(file))) {
       lineno++;
@@ -2471,7 +2471,7 @@ static int parseconfig(const char *filename,
       alloced_param=FALSE;
 
       /* lines with # in the fist column is a comment! */
-      while(*line && isspace((int)*line))
+      while(*line && ISSPACE(*line))
         line++;
 
       switch(*line) {
@@ -2487,7 +2487,7 @@ static int parseconfig(const char *filename,
 
       /* the option keywords starts here */
       option = line;
-      while(*line && !isspace((int)*line) && !isseparator(*line))
+      while(*line && !ISSPACE(*line) && !ISSEP(*line))
         line++;
       /* ... and has ended here */
 
@@ -2499,7 +2499,7 @@ static int parseconfig(const char *filename,
 #endif
 
       /* pass spaces and separator(s) */
-      while(*line && (isspace((int)*line) || isseparator(*line)))
+      while(*line && (ISSPACE(*line) || ISSEP(*line)))
         line++;
 
       /* the parameter starts here (unless quoted) */
@@ -2544,7 +2544,7 @@ static int parseconfig(const char *filename,
       }
       else {
         param=line; /* parameter starts here */
-        while(*line && !isspace((int)*line))
+        while(*line && !ISSPACE(*line))
           line++;
         *line=0; /* zero terminate */
       }
@@ -2852,7 +2852,8 @@ convert_from_network(char *buffer, size_t length)
 }
 
 static
-char convert_char(curl_infotype infotype, char this_char) {
+char convert_char(curl_infotype infotype, char this_char)
+{
 /* determine how this specific character should be displayed */
   switch(infotype) {
   case CURLINFO_DATA_IN:
@@ -2863,24 +2864,25 @@ char convert_char(curl_infotype infotype, char this_char) {
     if ((this_char >= 0x20) && (this_char < 0x7f)) {
       /* printable ASCII hex value: convert to host encoding */
       convert_from_network(&this_char, 1);
-    } else {
+    }
+    else {
       /* non-printable ASCII, use a replacement character */
-      return(UNPRINTABLE_CHAR);
+      return UNPRINTABLE_CHAR;
     }
     /* fall through to default */
   default:
     /* treat as host encoding */
-    if (isprint(this_char)
-    &&  (this_char != '\t')
-    &&  (this_char != '\r')
-    &&  (this_char != '\n')) {
+    if (ISPRINT(this_char)
+        &&  (this_char != '\t')
+        &&  (this_char != '\r')
+        &&  (this_char != '\n')) {
       /* printable characters excluding tabs and line end characters */
-      return(this_char);
+      return this_char;
     }
     break;
   }
   /* non-printable, use a replacement character  */
-  return(UNPRINTABLE_CHAR);
+  return UNPRINTABLE_CHAR;
 }
 #endif /* CURL_DOES_CONVERSIONS */
 
diff --git a/src/setup.h b/src/setup.h
index 1acd19e85..a8f636974 100644
--- a/src/setup.h
+++ b/src/setup.h
@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -184,4 +184,16 @@ int fileno( FILE *stream);
 #define strdup(ptr) curlx_strdup(ptr)
 #endif
 
+#ifndef ISSPACE
+/* typecasting craze to avoid negative number inputs to these macros */
+/* copied from lib/setup.h */
+#define ISSPACE(x) (isspace((int)((unsigned char)x)))
+#define ISDIGIT(x) (isdigit((int)((unsigned char)x)))
+#define ISALNUM(x) (isalnum((int)((unsigned char)x)))
+#define ISXDIGIT(x) (isxdigit((int)((unsigned char)x)))
+#define ISGRAPH(x) (isgraph((int)((unsigned char)x)))
+#define ISALPHA(x) (isalpha((int)((unsigned char)x)))
+#define ISPRINT(x) (isprint((int)((unsigned char)x)))
+#endif
+
 #endif /* __SRC_CURL_SETUP_H */
diff --git a/src/urlglob.c b/src/urlglob.c
index d5d3f4eae..ba4fb1eae 100644
--- a/src/urlglob.c
+++ b/src/urlglob.c
@@ -177,7 +177,7 @@ static GlobCode glob_range(URLGlob *glob, char *pattern,
   /* patterns 0,1,2,... correspond to size=1,3,5,... */
   ++glob->size;
 
-  if (isalpha((int)*pattern)) {         /* character range detected */
+  if (ISALPHA(*pattern)) {         /* character range detected */
     char min_c;
     char max_c;
 
@@ -205,7 +205,7 @@ static GlobCode glob_range(URLGlob *glob, char *pattern,
     pat->content.CharRange.ptr_c = pat->content.CharRange.min_c = min_c;
     pat->content.CharRange.max_c = max_c;
   }
-  else if (isdigit((int)*pattern)) { /* numeric range detected */
+  else if (ISDIGIT(*pattern)) { /* numeric range detected */
     int min_n;
     int max_n;
 
@@ -229,9 +229,11 @@ static GlobCode glob_range(URLGlob *glob, char *pattern,
 
     if (*pattern == '0') {              /* leading zero specified */
       c = pattern;
-      while (isdigit((int)*c++))
+      while (ISDIGIT(*c)) {
+        c++;
         ++pat->content.NumRange.padlength; /* padding length is set for all
                                               instances of this pattern */
+      }
     }
 
   }
@@ -498,7 +500,7 @@ char *glob_match_url(char *filename, URLGlob *glob)
     return NULL; /* major failure */
 
   while (*filename) {
-    if (*filename == '#' && isdigit((int)filename[1])) {
+    if (*filename == '#' && ISDIGIT(filename[1])) {
       unsigned long i;
       char *ptr = filename;
       unsigned long num = strtoul(&filename[1], &filename, 10);