What a pain?! Apparently, network-manager-pptp doesn't work in gutsy, and I even had issues with pptpconfig... I ended up writing shell scripts to start and stop my vpn, and everything is happy now...
Here are some links which helped me to figure out the configuration for work:
I paid attention to the configuring-by-hand sections, as none of the others worked for me. Plus, the amazing staff at St. Olaf College IIT!
With a little side of applesauce...
©2006 Shannon Eric Peevey