As I mentioned earlier in classroom training at Orlando, we ran into AAC upgrade issue where the server connections are lost after the upgrade. Please find below APAR and Fix notes from IBM. IBM is releasing the fixpack in 9.0.5 to fix this issue.
Those who are running in to upgrade issues with ISAM or AAC modules, please post them here.
http://www-01.ibm.com/support/docview.wss?crawler=1&uid=swg1IJ03427------------------------------
VishnuVamsi Bathula
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