Spring Portlet Unregisted by PortletHotDeployListener

[Kamal Hossain，修改在12 年前。]

I have a spring portlet it working fine. but problem is when i restart tomcat some how protlet unregistered by liferay. i am using liferay 6.0.5. when i redeploy portlet again it start working as expected.

here is the log:
16:44:56,469 ERROR [HotDeployUtil:192] com.liferay.portal.kernel.deploy.hot.HotDeployException: Error unregistering plugins for template-design-tool
com.liferay.portal.kernel.deploy.hot.HotDeployException: Error unregistering plugins for template-design-tool

16:44:56,471 INFO [ExtHotDeployListener:205] Extension environment for template-design-tool will not be undeployed
16:44:56,471 INFO [PortletHotDeployListener:404] Unregistering portlets for template-design-tool
16:44:56,484 INFO [PortletHotDeployListener:435] 1 portlet for template-design-tool was unregistered