Failed to download pxe variable file

Been having some trouble with my lab.  I have the issue described here:

http://blogs.technet.com/b/smsandmom/archive/2008/08/26/configmgr-2007-osd-deployment-errors-out-within-a-few-seconds-after-winpe-loads-and-then-automatically-reboots.aspx

However, i do have a valid IP address.  All the logs look good (winpeinit.log and smsts.log) smsts.log just shows the following:

Failed to download pxe variable file. Code(0x00000001)    TSPxe 
PxeGetPxeData failed with 0x80004005    TSPxe

I've searched and haven't been able to find any additional information.  Any suggestions?