Try my scripts, which I posted to this list a few weeks ago. Mac OS X uses /etc/resolv.conf, I believe, so they should work for you, too. Search the archives for my messages, with instructions.
Have fun, Jesse -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Jesse Adelman http://www.boldandbusted.com/ -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+