I suggest a new plugin, JIRA integration for Openproj (Serena). It's a free, open source tool, that came to replace Microsoft Project's "hegemony". We start to use JIRA and Openproj some time ago, and we believe that this integration can add a plus to JIRA's feature, since Openproj is open source. When searching google and several forums, I found little information about this integration.

Thanks for your support!