While Geronimo server startup, Bean Scripting Framework (BSF) tag library descriptor that included in bsf-2.3.0.jar isn't parsed correctly and Confluence startup fails.
The root cause is that the element "short-name" value in the BSF tld contains a half space character.

Related information:
Apache Geronimo User ML - deploying BIRT sample in AG V2,0 M6 fails
http://www.nabble.com/deploying-BIRT-sample-in-AG-V2-2C0-M6-fails-to12013748s134.html

I recommend that BSF taglib binary (bsf-2.3.0.jar) should be rebuilt.

Thanks,
Kan Ogawa