Here is what i have done:
I have been using my Google Apps username (XXX@XXX.com) which can be used to redirect to the Google Account that i have on the Gmail (XXX@gmail.com) for the Google services that aren't provided for hosted domains.
The previous orders have been charged on the Gmail Account (XXX@gmail.com) since there can't be a Google Checkout Account on a Google Apps domain.
Yesterday when i set up the phone i used the Gmail username, and after searching those apps it asked for payment.
So, what is wrong with all this? Since the apps are bought in the
XXX@gmail.com email, what is the problem with Android Market?
I also have to say that i use market enabler since i live in a non-supported country and faked to the US carrier.
This is really troubling :S
I contacted the support of one of the apps and they advised to buy again and they will refund the previous charge.
Unfortunately this is not a good solution even though it is fair :|