Oh did I den to response to myself to get karma point ??
I really got bitten by this issue... I installed one plugin, and immediately my site went down.
Does the upgrade script(s) check to see if the db has all of the required tables and create them if necessary?
Also, would it be possible to update the Database Schema Guide (http://www.jivesoftware.com/builds/docs/clearspace/latest/DatabaseSchemaGuide.html) to the current schema as the jivePluginProp table is NOT listed there.