diff -r 60a124678842 -r 61f65dd6eeb9 lib/iec_types.h
--- a/lib/iec_types.h	Sun Jan 04 17:21:33 2009 +0100
+++ b/lib/iec_types.h	Sun Jan 04 17:23:06 2009 +0100
@@ -52,7 +52,7 @@
 #endif
 
 #ifndef STR_LEN_TYPE
-#define STR_LEN_TYPE uint8_t
+#define STR_LEN_TYPE int8_t
 #endif
 
 typedef STR_LEN_TYPE __strlen_t;