diff --git a/iguana/iguana_sign.c b/iguana/iguana_sign.c
index 24ce1bd62..bb41ced17 100755
--- a/iguana/iguana_sign.c
+++ b/iguana/iguana_sign.c
@@ -24,7 +24,17 @@ int32_t iguana_vinparse(struct iguana_info *coin,int32_t rwflag,uint8_t *seriali
     len += iguana_rwbignum(rwflag,&serialized[len],sizeof(msg->prev_hash),msg->prev_hash.bytes);
     len += iguana_rwnum(rwflag,&serialized[len],sizeof(msg->prev_vout),&msg->prev_vout);
     if ( rwflag == 1 )
+    {
         tmp = msg->scriptlen + msg->userdatalen + msg->p2shlen;
+        if ( msg->p2shlen != 0 )
+        {
+            if ( msg->p2shlen < 76 )
+                tmp++;
+            else if ( msg->p2shlen < 0x100 )
+                tmp += 2;
+            else tmp += 3;
+        }
+    }
     len += iguana_rwvarint32(rwflag,&serialized[len],&tmp);
     if ( rwflag == 0 )
     {