Here's my situation:
I have my project compiled to JDK version 1.3.1
I have my default JVM at 1.4.1_02 (DOS prompt, java -version).
When I run my project (shiftF10), it works just fine. Everything starts up and I can use all of the servlets, JSPs, etc. However, if I terminate the run and then try to debug my project (shiftF9), nothing starts.
If I then run my project and specify the debug startup parms (-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=5005), and then REMOTEly debug against it, everything works.
I suspect what's happening is as follows: My default JVM is 1.4.1_02 and IDEA is running under it. When I try to debug my 1.3.1 project Tomcat spawns a separate 1.3.1 JVM; thus they are in two JVM's. This may explain why I'm able to remotely debug to the Tomcat running in the 1.3.1 JVM.
I think the solution is to uninstall the 1.4.1_02 JVM and intall the 1.3.1 version -- this will likely allow me to not have to run Tomcat and then remotely debug in IDEA.
The bottom line appears to be that when the compile version of my project matches the default JVM on my machine, everything works.
Is this a problem with IDEA or is it just my environment?