If you already created your XDoclets configurations and have the "Enable XDoclet" options checked, uncheck that option, apply changes and click OK. Now go back into the XDoclet config and check the "Enable XDoclet", apply changes and click OK.
I had the same issue and the above is what I did to resolve that problem. Similar procedures required if the "Run packaging" option is greyed out.
Yes, it is working fine now. Thanks for replying! :)