--- packet-h225.old.c	2004-02-11 21:55:02.000000000 +0100
+++ packet-h225.c	2004-02-13 13:42:48.564938000 +0100
@@ -1940,7 +1940,7 @@
 
 	h221NonStandard = ((t35CountryCode * 256) + t35Extension) * 65536 + manufacturerCode;
 
-	proto_tree_add_uint(tree, hf_h221Manufacturer, tvb, (offset-3)>>3,4,h221NonStandard);
+	proto_tree_add_uint(tree, hf_h221Manufacturer, tvb, (offset>>3)-4,4,h221NonStandard);
 
    	return offset;
 }