Not sure how it will effect you since the accounts are in two different stores, but here is article that explains how to use multiple accounts with one iphone. I have done this myself, but we are both signed up to US accounts.

http://www.everythingicafe.com/quick-guide-one-iphone-multiple-itunes-accounts/2010/03/25/

Maybe you should post on the Apple Support discussions forum on Apple site.

http://discussions.apple.com/index.jspa

Hope this helps.
joan

--- In apple-iphone@yahoogroups.com, baileyq <baileyq2000@...> wrote:
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> I just got an unlocked iphone here in germany and i can't purchase any new apps because my previous iphone/itunes account is a u.s. one.  unfortunately my asus laptop -only 6 months old, btw--the charger died (look up charger issues if you ever plan to buy an asus anything!) which I didn't realize until the battery was almost dead, so I can't access itunes from a computer that is authorized.
>
> my new phone is activated and working, and I can ceate a new account here in germany, but I don't know how that will affect my other purchases and/or access to certain apps.  and costs of things.  I had been able to use my vpn to access itunes from my laptop to purchase stuff before.
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> thanks for any avice on this.  I'm afraid that if I set up a new account here in germany, it'll mess up what I already have also.
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