Wow this was a real mission for me and a learning experience... I'm updating you from my OpenSolaris box right now :).....  Essentially in a nutshell, I had to run /usr/X11R6/bin/scanpci -v to find out what typ of network card I had installed (NVIDIA MCP61). I then googled that on the net and it returned this wonderful link "http://homepage2.nifty.com/mrym3/taiyodo/nfo-2.6.0.tar.gz"  . This driver was the missing link in my quest to get networking.

I will create  a tutorial on howto setup networking under OpenSolaris in a few hours after I get a nap.