This was originally noted by Aaron Belovsky back in July of 2007.
When calling the Room method, requestAffiliations(), an Unknown Property Error will be thrown since the callback method (finish_requestAffiliates()) is private and inaccessible by the IQ object.
A workaround is to set the callback method’s access modifier to public instead of private.
This is not the best solution, possibly rewrite to use events instead of callbacks, but it does work.
Other private callbacks could have the same issue.