diff -ruN libcgi-1.0-orig/src/string.c libcgi-1.0/src/string.c
--- libcgi-1.0-orig/src/string.c	2003-12-15 10:42:26.000000000 +0000
+++ libcgi-1.0/src/string.c	2007-01-02 00:20:51.000000000 +0000
@@ -584,7 +584,7 @@
 
 	va_start(ptr, s);
 
-	va_copy(bkp, str);
+	va_copy(bkp, ptr);
 	len = strlen(s);
 
 	while (*str) {