This might look like a stupid post but it took me 20 minutes to be done! I was trying to configure tomcat 6 for remote debugging with Eclipse in Windows.
The only catch was putting: "-Xdebug" and "-Xrunjdwp:transport=dt_socket,address=8000,server=y,suspend=n" in two different lines, without qoutes in tomcat6w.exe > Java tab > Java Options (before everything else) and apply.
Then you just need to configure a Remote Java Application profile in Debug Configuration of Eclipse for your project and point it to the same jpda port.
