For XQilla 2.1.2, Xerces-C 2.8.0 is required with the patches from the xqilla/src directory. I'm working with the Xerces-C guys to get the patches included in Xerces so that patching it won't be necessary.
Is this Library active? Are bugs on Sourceforge being noticed? Are all the developers on holiday?
https://sourceforge.net/tracker/?func=detail&aid=2703260&group_id=152021&atid=782848