AD Schema Extension

I'm almost there, I can taste it... I followed the steps in another thread, and extended my schema. I can see the new classes in attributes in the MS schema editor. However, when I use a 10.5 client, bound to the AD and attempt to save say... finder preferences against a user object, I keep getting error -14142, schema class violation. I'm not sure where I went wrong here, perhaps the class types are wrong. Has anyone dealt with this? Thanks in advance, Tom