Returns the NLS'ed message for the given argument.
@param key the key to look up @return the message for the given key
@exception IllegalArgumentException <ul> <li>ERROR_NULL_ARGUMENT - if the key is null</li> </ul>
See Implementation
Returns the NLS'ed message for the given argument.
@param key the key to look up @return the message for the given key
@exception IllegalArgumentException <ul> <li>ERROR_NULL_ARGUMENT - if the key is null</li> </ul>