Fallback to message-destination-type

I have two MDB's that have no activation config. They actually don't need one as the only relevant information is the destination type which is already stated in the message-destination-type tag.

Nevertheless I get the following message for these two MDB's:

No message-driven-destination given; using; guessing type

When I add the activation-config this message vanishes.
Therefore I suggest to use the message-destination-type in case the 'destinationType' property is not present in the activation config (or the activation config is missing).