Server Side serial port access in GWT with RXTX

I've been looking around for a succinct answer on this one, but I have
been reading conflicting comments. I want to use the RXTX package on
the Server-Side only to access my serial port (I realize there are
access restrictions on the client side anyway). Some say that you can
just put the .jar into the war/blah/lib directory, others say that you
can reference from an external server like Tomcat (yeah, I don't know
what that means yet). At present I am getting the "is not supported
by Google App Engine's Java runtime environment" for my server side
implementation of the Serial Port Access service I am creating. Can
anyone in the ether help a rookie to GWT?

--
You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group.
To post to this group, send email to google-web-toolkit@googlegroups.com.
To unsubscribe from this group, send email to google-web-toolkit+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=en.