[hibernate-dev] patching javassist - which ver?

Hello, Long time listener, first time caller here - thanks for an excellent framework. We've been profiling our Hibernate 3.6.10-based app and noticed a perf bottleneck in javassist.util.proxy.RuntimeSupport.find2methods. Unfortunately, this method, which has a synch. block, is being called on every invocation of every proxied entity method (see javassist.util.proxy.ProxyFactory.makeForwarder(), called indirectly by ProxyFactory.createClass()). In our testing, the result is that our service call's latency increases from 33 to 55, 260, 400ms as concurrency increases 1-10-20-30 users on a 4-core CPU. At 20 and 30 users 51% of CPU time is spent contending for a monitor in RuntimeSupport.find2methods. Since find2methods merely interrogates class metadata, seems like its return values should be cached (in a ConcurrentMap?). Since this is a big problem for us, I am happy to submit a patch to javassist, but would like to know which version should I be patching, given that I am primarily interesting in using javassist in conjunction with Hibernate? Currently, hibernate-core 4.1.1 uses javassist 3.15.0-GA, 3.10.Final uses 3.12. Latest GA is 3.16-1. I'd appreciate any other advice as well (perhaps this problem's been discussed?) Thank you, -nikita