Make sure that the jar with the static HashMap has not been copied into either of the WAR file's WEB-INF/lib directories by mistake.
You are correct. We have same class in two jars which caused the issue. Now it is resolved.
If you have any clue can you clarify this question? why having same classes in two jars didn't fail in 4.2.3a? Could it be because single class loader loads all jars?
Thanks for your help and time.