OptimizerFactory - ThreadLocal not cleared

The OptimizerFactory is using ThreadLocals to store the threadOptimizer. However - the stored Locals are not cleared after usage.
Using HeapDump Analysis you can see that e.g. in Tomcat the classloader can not be garbage collected, because the optimizer (e.g. the ASMAccessorOptimizer or any other one) is stored in a thread local.
Maybe you can provide some code fix to clear this one or maybe its possible not to use them - don't know whats best here.