diff --git a/string.c b/string.c
index b38c83ad60..d4f3be052b 100644
Binary files a/string.c and b/string.c differ
diff --git a/string.h b/string.h
index c795b3336d..d5f637719e 100644
--- a/string.h
+++ b/string.h
@@ -43,7 +43,7 @@ typedef enum CharSetFilter {
 	CS_ALPHA,             //! Only alphabetic values
 } CharSetFilter;
 
-/** Convert the given string to lowercase */
+/** Convert the given string to lowercase, only works with ASCII! */
 void strtolower(char *str);
 
 typedef uint32 WChar;