Recently, I was helping a client upgrade their Oracle WebCenter Interaction portal from 6.1 to 10gR3 in a Solaris environment.  Yes.. this post applies mostly to Solaris installations only, so feel free to stop reading here ... I won't be offended :)

Most of the upgrade was fine, but one of the servers in this test environment had both Publisher 6.4 and Search Server (10gR3) on the same machine.  Publisher was not upgraded, but after upgrading search server to 10.3.0 , Publisher reported errors while connecting to the search server on its diagnotics page:

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