You are saying about only single VLAN 67. With "sh ipx server" command, we can view only servers like file or print, but not all clients and depends on SAP ACL's in between the server advertisements cann't be forwarded further. So that, it cann't learned by 7200 for VLAN 67 servers. Because of this problem is only for a VLAN, check where the SAP advertisements getting blocked.