I'll just toss in here that the Xfce guys have moved to a new conf
system called (unsurprisingly) 'xfconf'.
http://spuriousinterrupt.org/journal/archives/2008/10/06/2008/
http://mocha.xfce.org/~kelnos/xfconf/docs-current/
Might be worth looking at for some of your needs.
kevin