VMWare, Netware 6.5 SP6, and Zenworks 7 SP1, IR4

[allenflame]

I just built a new Zenworks server for our school district. I reimaged a lab fine, no problems at all. I moved on to one of the schools and about half way through the imaging, the server abended. I seems to be a problem with TFTP, since it abends whenever the machines are booting to linux shell, and not while they're actually imaging. I also tried this morning to remote wakeup a couple of groups of workstations, and about 2 minutes into waking them up, the server abended again. I decided to go back to the original tftp files that came with IR4 and this time NWTS caused the abend. We're running VMWare ESXI. There are 4 Quad Core processers, and 16 Gig of ram. Any suggestions on what I should check?