GNU make 3.80/3.79.1: Pattern rule broken?

[amontse]

Hi,

I have the following makefile that the gnu make (3.80 and 3.79.1)
behaves in a unpredictable way:

XX_%ExGw_mt : XX_%ExGw

XX_%Gateway : XX_%ExGw

XX_%ExGw :
       touch foo.c

If you try make XX_ABCExGw_mt, GNU make correctly derives the rule and
execution the touch statement.

If you try make XX_Gateway, GNU make fails with the message "No rule to
make target XX_ABCGateway".

Is the GNU make broken on pattern rule or is there any syntax error in
my makefile?

Thanks for your advice and help in advance.

Amon