Problem with iTunes, Please help!!!

[povsicf]

I have an iPhone 3GS and I recently switched from my powerbook to a new macbook, therefore I had to authorize each computer to allow itunes to sync all my applications and anything from the app store. Well my account shows that I have 4 authorized computers and I just reinstalled leopard on my computer today since I was having problems with it, and now when I go to authorize the computer I get an error message saying that there was an error with the permissions, and that I need to try it again or deauthorize the computer. Well I tried botha and nothing seems to work. I don't have access to all the other computers to deauthorize, so how do I get it so that I can authorize this computer to sync the apps and so forth. please help me.