An interface defining the contract for interaction with
the JwmaPreferences model.
JwmaPreferences allows a view programmer to obtain
information about the users preferences to display
them for reading or editing.
author: Dieter Wimberger version: 0.9.7 07/02/2003
Returns the JwmaMailIdentity with the given
unique identifier. If the identifier is invalid,
the method will return the default mail identity.
Parameters: uid - a unique identifier of a mail identity. the JwmaMailIdentity with the given uid.