EZD and Protools

I was testing ezd on protools 7.1!
It works great, I write my midi track and then I play it through EZD, no problems works smooth!
Then my Bro was asking me if I can create a session with just an empty midi track and EZD active on that track so he can load that session, hook up his electronic drum kit and play through ezd instead of the samples on his Yamaha DTX 2.0.
I can't get that shit working, I make the midi track record-enabled but no sound is coming from the midi track if I hit a pad!
I do the very same thing on Cubase SX3 and it works like a charm!!
I played with the input only monitoring/auto input monitoring, I don't get a sound :(
Fuck I can't get it work.