Mt.Red vardiff not working? vardiff set to 2, but still receive only diff1 share

[calonew]

Hello bitcoin comunity, I wonder if anyone can help a newbie here...

It seems mtred.com pool completely ignores the vardiff settings in worker setup.
I have a worker with vardiff setup to 2, but when worker is connected to mine.mtred.com, it only receives diff 1 shares.

Please note that I did not use '0' dynamic difficulty on worker setup -- I used '2' for difficulty, which was supposed to set the difficuly to 2.
But, somehow the difficulty is ignored, and I still get only diff 1 shares...

Is anyone experiencing the same problem? Is this a bug?
Thanks for any help or information!