This issue is easily solvable in JBoss5, where the deployers have more flexible architecture.
You should open a jira issue so that people can discuss whether it makes sense to support in this in the 4.x codebase. The proposal you suggest sounds fine.
I created the Feature request at http://jira.jboss.org/jira/browse/JBAS-5168.
If I may, I have another request but this time regarding the AbstractWebDeployer.
Still regarding sip servlets, sip servlets can be converged applications. It means that they can be an HTTP+SIP application and that servlets from both side can play togehter nicely and are tighly integrated by sharing the same context and others objects and as such seen as a web application. They can be packaged as a war or sar. The specification establishes the equivalence of .sar and .war archive formats in the context of SIP Servlet containers so that a .war archive should also be able to contain sip application components and a .sar archive should be able to contain web application components.
As such we really need to extend the AbstractWebContainer or for that matter the JbossWeb component to fully leverage the exsiting code allowing web deployment rather then duplicating it and going into maintenance nightmares.
But this is not currently possible since the AbstractWebContainer uses hardcoded values to check for .war extension in its init() method and parseMetaData() method.
It could be made flexible and allowing for any extensions quite easily (instead of checking lastIndexOf(".war") rather check lastIndexOIf(".") ?). This way we could deploy war or sar leveraging the existing Jboss code.
Do you think that would be possible ?
If so should I create a Jira Issue too ?