Remote debugging with JBuilder is a pain in the neck. I would suggest BugSeeker, which is cheaper than JBuilder Enterprise and much much better. To setup tomcat modifoy tomcat.bat ( .sh ) in the way that it can accept remote connection from debugger: %_STARTJAVA% -Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,address=8000,server=y,suspend=n %TOMCAT_OPTS% -Dtomcat.home="%TOMCAT_HOME%" org.apache.tomcat.startup.Tomcat %2 %3 %4 %5 %6 %7 %8 %9 in the example above tomcat is going to start and accept socket connection on port 8000. You will also need to setup your remote debugging project in JBuilder. Again, if you would decide to use BugSeeker, you will be able to choose remote debugging project and specify host name where your debug tomcat is running and port. good luck.