diff --git a/src/ChangeLog b/src/ChangeLog
index 25e41d94..1c444eb3 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2005-05-05  Hrvoje Niksic  <hniksic@xemacs.org>
+
+	* url.c (url_unescape): Don't unescape %00, it effectively
+	truncates the string.
+
 2005-05-05  Hrvoje Niksic  <hniksic@xemacs.org>
 
 	* log.c (copy_and_escape): Replace the FOR_URI argument with a
diff --git a/src/url.c b/src/url.c
index e89704d7..f77d8ad9 100644
--- a/src/url.c
+++ b/src/url.c
@@ -175,10 +175,16 @@ url_unescape (char *s)
 	}
       else
 	{
+	  char c;
 	  /* Do nothing if '%' is not followed by two hex digits. */
 	  if (!h[1] || !h[2] || !(ISXDIGIT (h[1]) && ISXDIGIT (h[2])))
 	    goto copychar;
-	  *t = X2DIGITS_TO_NUM (h[1], h[2]);
+	  c = X2DIGITS_TO_NUM (h[1], h[2]);
+	  /* Don't unescape %00 because there is no way to insert it
+	     into a C string without effectively truncating it. */
+	  if (c == '\0')
+	    goto copychar;
+	  *t = c;
 	  h += 2;
 	}
     }