I have a web application deployed to a remote resin server, and it has JMX turned on.
I can telnet to the remote server i.e
franz@see:/tmp$ telnet &l
If your application is running on JDK 1.6 then you should be able to connect it. If it is using JDK prior to 1.6 then run it with specifying the following JVM argument
-Dcom.sun.management.jmxremote