diff -urN gpxe-0.9.7/src/net/udp/dhcp.c gpxe-0.9.7-xnbauserclass/src/net/udp/dhcp.c
--- gpxe-0.9.7/src/net/udp/dhcp.c	2009-03-01 21:23:42.000000000 -0500
+++ gpxe-0.9.7-xnbauserclass/src/net/udp/dhcp.c	2009-08-21 11:23:09.000000000 -0400
@@ -78,7 +78,7 @@
 		       'A', 'r', 'c', 'h', ':', '0', '0', '0', '0', '0', ':',
 		       'U', 'N', 'D', 'I', ':', '0', '0', '2', '0', '0', '1' ),
 	DHCP_USER_CLASS_ID,
-	DHCP_STRING ( 'g', 'P', 'X', 'E' ),
+	DHCP_STRING ( 'x', 'N', 'B', 'A' ),
 	DHCP_PARAMETER_REQUEST_LIST,
 	DHCP_OPTION ( DHCP_SUBNET_MASK, DHCP_ROUTERS, DHCP_DNS_SERVERS,
 		      DHCP_LOG_SERVERS, DHCP_HOST_NAME, DHCP_DOMAIN_NAME,