I also faced the same problem, but when I shifted to Eclipse 3.1.2 the problem is solved.
Which JBoss IDE version are you using?
i'm using the JBoss IDE 1.6.0.GA
In that case there are 3 ways to solve your problem.
1) Either u move to Eclipse 3.1.2
2) Use JBoss IDE 2.0.0
3) Patches are avaialble for upgradation (not sure abt this)
See this thread for more information regarding JBoss IDE compatibility.
oh, i thought i was using the latest JBoss IDE version... but since i'm getting it from http://download.jboss.org/jbosside/updates/stable/ i have the latest stable version...
anyway, i found another way to work things out... since i dont really need to debug just yet and i just wanted to have control of the jboss from inside the eclipse i updated yhe eclipse with a plugin (not sure which one did it though) that lets me have J2EE prespective including a servers tab so this works out great for me...
i'm new to jboss and to the eclipse so i'll take my time and start by working the hard way till i get things right...
thanks a lot for your help, i hope that there will be a stable jboss ide 2.x when i'll need it :)