Null pointer Exception Exception after upgrading Weblogic 8.1 to Weblogic 10.3

We have upgraded our application from Weblogic 8.1 to Weblogic 10.3. After upgeade, we are getting the following exception randomly.
"Nullpointerexception at weblogic.servlet.internal.servletrequestimpl sessionhelper.initsessioninfo(ServletRequestImpl.java:2611)"
Please help me why this occurs.

Thanks.

Hey Karthik,

This is not the complete stack trace, which would not help identifying/resolving the issue. Post the stack trace... (Please be sure to use the code tag while posting the same).

As far as I can guess, this issue is caused due to any of your deployed application; you might be trying to use a request object where it is not in the scope. I cannot comment any further.

If you ask me, why this error was not there in your 8.1 env. , well we will find that out once you post the stack trace.

FYI:

Each request object is valid only within the scope of a servlet’s service method, or
within the scope of a filter’s doFilter method. Containers commonly recycle
request objects in order to avoid the performance overhead of request object
creation. The developer must be aware that maintaining references to request objects
outside the scope described above is not recommended as it may have indeterminate
results.