Has anyone here seen the following problem?

We have two OES clusters, one OES Netware and one OES Linux.

We just installed SP4 onto the Netware cluster from SP3. Since then the
OES Linux cluster has stopped working, it seems to have wierd SBD
issues. The Linux boxes are not edirectory replicas and I was wondering
whether the updated eDirectory on Netware could have broken Linux
clustering. When each node comes up they both claim to be the master
and both try to run the cluster services which stay in Quorom wait and
then go comatose. For now i've had to shut the linux clustering down

Anyone seen this before or have any suggestions?