Hi raghu,
by the espec, the container may destroy bean instance if the instance does not meet the requirements for serialization after ejbPassivate, therefore the container may throw an exception if you leave non serializable things like you sad !!! ...
hope this help.
Paulo Nunes (Brazil)
MCP OCP IBM285
SCJP 1.4 SCWCD 1.4 SCBCD 1.3