the size of your deployment archive does NOT influence application portability nor does it have any influence on how "heavy" the application is.
Get your terminology right.
Choosing your libraries based on their size is foolish to say the least. You should choose them solely on the functionality they provide.
What does reduce your portability is the use of applicationserver specific client libraries, but that's only a problem if you plan to support several application servers on a single client version as that would require a separate deployment for each (or deployment of the client libraries for each).
JMS will always require some sort of library. And those libraries will depend on the JMS stack you're planning to talk to.
But that shouldn't be a reason to not use it, as your idea that you should select your technologies solely on the size of their jarfiles is idiotic.
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