My PC Bubu Abasi is level 4 and has not had any problems until today, when I received the message "Your chosen deity does not support your class" and was unable to cast any spells.
Class: Druid
Deity: Osiris
Osiris is not on our list of druid deities, located here (http://www.escapefromunderdark.com/forums/showpost.php?p=1200&postcount=2).
Strangely, the deity information we have posted for Osiris (//%22http://www.escapefromunderdark.com/forums/showpost.php?p=1151&postcount=8%22) indicates that druids are among his worshipers.
This may be an oversight, which will require us updating one post or the other. I don't know which it will be, yet.
We should probably add them to the list of nature deities.
In either case, it strikes me as odd that it worked fine until today (unless there were recent changes, in which case that would explain it).
As a side note, in a rather blatant attempt to keep my concept viable, I offer that Faiths and Pantheons definitely list Druids among Osiris's followers, as also noted in the FR Wiki here (//%22http://forgottenrealms.wikia.com/wiki/Osiris%22). So at least we have a canon reference to hopefully push the decision makers over to my side of the fence ;)
[Edit: Howland has beat me to the punch, Hooray! :D]
It should have worked fine up until about a month ago. It should work fine again after the next reset, too.