Can I charge for closed source J2EE .ear module relying on GPLed EJBs?

Question

A customer asked me to add a (fairly generic monitoring and notifications) functionality to the in-house solution he has assembled on top of JBoss and couple of GPL-licensed components (downloadable from the open source vendor as EARs). I am using JMS and JMX to communicate with these components. Do I have to provide the source and redistribution rights to my customer to satisfy GPL restrictions? In other words, does configurable code that uses JMX and JMS mechanisms constitutes a derivative work? I would actually prefer to open source my code, but part of it relies on a patented third party logic that is unwilling to GPL it, but would gladly supply it to this customer. I am not asking for a legal advice, just for the opinion in terms of best practices / fair use.