xwiki backup / database conversion

hi! im trying to install xwiki on few enviromnents and then choose one that suits best xwiki needs. im using mysql and postgresql databases and i have _great_ problem with sensible performance testing because example mysql database provided on xwiki website cannot be converted into postgresql. also dump provided for PostgreSQL doesnt work with current xwiki release... :( as there is no backup facility built into xwiki (while it should be standard) i cannot use simpliest method of data conversion. i think that backup would be very very helpful feature, not only for making backups (in xml) but also for transferring xwiki into different environments! maybe developers could look at http://dbunit.sourceforge.net/ can anyone share xwiki database dump both in MySQL and PostgreSQL format? greetings! tomek