I have seen something similar when the patched remoting 2.2.2.SP1 jar is not used on the client side.
Are you sure you have
a) Dropped the jar into the server/<your config name>/lib directory on the server?
b) Added the jar as the first entry on your client classpath?
I did distribute the patched jar to the client and it is first in the classpath.
BUT in a late-night cut-and-paste accident I copied the jar to the default instance and not the messaging instance. After doing that the problem was solved.
Thanks for your help