appendEnries / Multirequest Bug

Hey

When i append an entry to a mix, i'm getting an exception - failed to unserialize server result
the entry is appended but it throws this error on return.

The big problem i am having is that when i try to do a multirequest it only does the first item, so i'm guessing there is an issue with the return value from the CE server

using the latest php client
php 5.2
ubuntu 10.04 server

any pointers would be great