Hi, FYI; Just complete full 6-CURRENT update. Now all nfs mounts (used 
to be rw) stays read-only.
/sys/nfsclient/nfs_vfsops.c:
     $FreeBSD: src/sys/nfsclient/nfs_vfsops.c,v 1.175 2005/05/17 
12:00:43 des Exp $
BTW. Commit log do not match actual change.
Alexander.