RULE hint better sometimes after 10.2.0.3 upgrade

We just upgraded our HP-UX 2 node RAC database from 10.1.0.5 to 10.2.0.3.  

So far, I have come across 2 queries where performance died. On both queries, running it with the RULE hint brought performance back. There were no hints on the queries before. Also, on one of those queries, deleting all stats on the object greatly improved performance (but on the other it made no difference).  

So, did the optimizer change that much between 10.1.0.5 and 10.2.0.3?  

I know the RULE isn't supported in 10g, but it can be used.  

Am I missing anything obvious?  

Also, on this upgrade the JVM crapped out, although the status and all was valid. After reinstalling it, all was fine.            

John Fedock

"K" Line America, ISD Department  

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