Yo. For all my mail accounts I checked YAMN option "Use contact notification for this account". All worked well at first, but after I turned my Facebook proto to "Invisible", my "mail contacts" seems to act just like they belong to Facebook now - so, they turned to invisible too.
If I set Facebook's status to "Online", YAMN mail contacts will show up again. So, now I'm forced to use "Online" always.
I also tried to see what will happen if I pick "offline" for Facebook, and that doesn't affect YAMN mail contacts. Also, once I made wrong set up for an mail account, and Facebook didn't affect that one too.
So, seems like Facebook's "invisible" status affects all the properly created (green icons) YAMN mail contacts on the Miranda NG's contact list.
Edit: I just tried one another trick. I created separated group for YAMN contacts, and moved them there. But god damn Facebook still affects them.
And, damn, even MSN's status does the same thing.