diff --git a/scan_asn1BOOLEAN.c b/scan_asn1BOOLEAN.c
index 99bb7c1..a659103 100644
--- a/scan_asn1BOOLEAN.c
+++ b/scan_asn1BOOLEAN.c
@@ -8,7 +8,7 @@ size_t scan_asn1BOOLEAN(const char* src,const char* max,unsigned long* val) {
   long ltmp;
   if ((tmp=scan_asn1int(src,max,&tc,&tt,&tag,&ltmp)))
     if (tc==UNIVERSAL && tt==PRIMITIVE && tag==BOOLEAN) {
-      if (ltmp!=0 && ltmp!=1) return 0;
+      if (ltmp!=0 && ltmp!=255) return 0;
       *val=(unsigned long)ltmp;
       return tmp;
     }