diff --git a/include/curl/curl.h b/include/curl/curl.h
index abfe3e523..cf96c326d 100644
--- a/include/curl/curl.h
+++ b/include/curl/curl.h
@@ -561,15 +561,26 @@ enum {
 
 
 typedef enum {
-  TIMECOND_NONE,
+  CURL_TIMECOND_NONE,
 
-  TIMECOND_IFMODSINCE,
-  TIMECOND_IFUNMODSINCE,
-  TIMECOND_LASTMOD,
+  CURL_TIMECOND_IFMODSINCE,
+  CURL_TIMECOND_IFUNMODSINCE,
+  CURL_TIMECOND_LASTMOD,
 
-  TIMECOND_LAST
+  CURL_TIMECOND_LAST
 } curl_TimeCond;
 
+/* for backwards compatibility */
+#ifndef TIMECOND_IFMODSINCE
+#define TIMECOND_IFMODSINCE CURL_TIMECOND_IFMODSINCE
+#endif
+#ifndef TIMECOND_IFUNMODSINCE
+#define TIMECOND_IFUNMODSINCE CURL_TIMECOND_IFUNMODSINCE
+#endif
+#ifndef TIMECOND_LASTMOD
+#define TIMECOND_LASTMOD CURL_TIMECOND_LASTMOD
+#endif
+
 #ifdef __BEOS__
 #include <support/SupportDefs.h>
 #endif