CFFaultException in WCF Windows Mobile client

Hello community,

Now i have a problem, the problem's name is "CFFaultException". I Expose two methods in a WCF Service hosted in IIS...the one takes a custom class
and stores it in the database, the other takes data stores them in a List and serves in the client....evertyhing works great on a desktop client
where i actually created the proxy module and shared it....but, there's always a BUT! things get creepy while i was trying to get and send data from a moblie device.

I Generated the proxy classes with NetCFSvcutil tool...what i first noticed..is the array[] use of MyClass and not List<> connection is succesfull, but even trying to get or send,
i keep getting this strange error "CFFaultException" where i don't have a clue what it is asking for...i suspect something about treating my objects as array while the service as List<>. But again, WCF transports them as arrays anyway...so im lost...i have included exception details in web.config....but gives me nothing to work on...everything is by rules, basichttpbinding etc.

Tried to create an operation in the service that returns a string and succesfully called...tried to call a void with integer parameter and failed with the same exception.

If anyone knows a solution on that or a nice guide about custom classes over WCF and mobiles with custom objects....

Thank you in advance....