Khalid,
If you click the MyEclipse menu, then the About MyEclipse item then Coniguration Summary and paste the result for me here, I’ll have a look.
Also try shutting down your app server, removing your deployment rebuilding your project then restarting MyEclipse using the -clean command line argument. Then after restarting recreate a new deployment to you app server and start it back up again and see if that helped.
Also are you debugging JSP or Servlets/Java code?