In previous version of ejabberd, it was not possible to add feature using the HTTP server included in ejabberd. The previous modules had to patch the ejabberd code to insert their own handlers. This was the case for the HTTP binding module and web presence module.
Two modules patching the same code, was making them mutually exclusive and not really compliant.

In the current SVN version, it is now possible to write your own HTTP plugin. You can now extend the behaviour of the ejabberd HTTP server by adding new handlers directly from the configuration file.
The HTTP binding module from ejabberd-module SVN has already been converted. to support this new feature:
https://forge.process-one.net/browse/ejabberd-modules/http_bind

If you want to convert your existing code or write new HTTP plugin modules, a new tutorial has been written to help you doing so:
http://www.process-one.net/en/wiki/ejabberd_HTTP_request_handlers/

Your comments, questions and improvements suggestions are welcome !