Oct. critical patches fail 2003 Server cluster..

Brief:

Running Windows Server 2003 Ent w/ SP1 & Windows Clustering.
Node1 and node2 in cluster, iSCSI attached SAN drives. Saturday,
production is fine, sunday, auto install of 7 "critical" updates. 8:00
am Monday, calls that drives controlled by the cluster are offline.
Reboot of Node1 failed to bring online, reboot of node2 failed to bring
online, uninstall of patches on node 2 failed to bring online, reboot
of node2 after removal of patches failed to bring online, uninstall of
updates on node1 w/ reboot (restore to pre updates status) brings all
drives online. Production restored to normal.

Has anyone else experienced this, if so did you possibly find the root
cause?

I am in the process of setting up a devt environment to test the
process of critical updates on a cluster environment, but I am easily a
couple of days away from getting any good data.

Any feedback appreciated.

Scarhead.