Dynamic MSMQ port error – ‘outbound transport could not be resolved ‘

In my configuration file i have the folloing as my queue destination path to be used on my dynamic send port.

• myQueuePath =    queue://FORMATNAME:DIRECT=OS:.\PRIVATE$\MyQuePath

In the orchestration (Expression shape) i have the following

• MyDynamicSendPort(Microsoft.XLANGs.BaseTypes.Address) = myQueuePath;

but im getting the following error:

• The outbound transport could not be resolved because a matching transport protocol prefix could not be derived from the URL “queue://FORMATNAME:DIRECT=OS:.\PRIVATE$\MyQuePath”.

Why am i getting this error? Any help would be greatly appreciated.

Thanks