t23745 ,
Debugging of JSPs are supported.
Can you give us some more information ?
1) Can you share your Operating System and version details ?
2) Is your WAS server started in Debug mode ? To enable the breakpoints and for execution to halt , the server must be launched in debug mode.Here are the links to FAQs for more information on debugging :
http://www.myeclipseide.com/documentation/quickstarts/appservers/#debugging
http://www.myeclipseide.com/documentation/quickstarts/blueedition/blue_connectors/#debug
http://www.myeclipseide.com/documentation/quickstarts/webprojects/#jsp_debugging
3) Switch to a new workspace , replicate the issue and check the .log file which is located at <workspace dir>/.metadata/.log for any errors of interest. If yes then paste the errors here.
4) I also recommend updating to the latest version of MyEclipse Blue 10 and check if you still see the issue. Take a look at this link for more info about download and features available in MyEclipse Blue 10 : https://www.genuitec.com/forums/topic/myeclipse-10-is-now-available/
5) If you are still seeing the issue, elaborate on the steps you are following.