We have a running instance of JIRA 4.2.1 with integrated SSO, now we are in a process of upgrading JIRA to 5.0.2 version. We have done almost all the required steps and JIRA 5.0.2 is running perfectly with existing database. But when I am deploying the existing SSO integration related files it redirects perfectly on SSO url but when it come back to JIRA it shows some error like "java.lang.AbstractMethodError". I have attached a screen shot of above error.
Thanks in Advance.