It's affecting to all the people who is upgrading to a non-valid 2.x ROM everywhere
HTC Hero dudes are having the same problems, and I found a solution here:
Apps missing from marketplace - Android @ MoDaCo
Maybe someone with more contacts around the HTC Hero groups can get more info about what's the market doing with these steps.
My theory is that the new Market has flagged us with a "special" state after checking that we were using a non-valid ROM (musty's). If this fix works, it seems that it can be easily solved logging again into your account with a good ROM (i.e. with a Droid). Then, Google consider us again as normal users.
Also, just my thoughts, this does not work returning to IK4/IK5 ROMs because they are using the old market. I hope that creating an AOSP 2.x build for Galaxy (with a good signature and who knows what more) will fix our accounts