Here is the answer to the mail I sent them!!!
Thanks for all your help folks!!
Dear Geoff,
I understand that you have an iTunes Gift Card that was purchased in the U.K., and would like to know how to use it on the German iTunes Store.
The iTunes Gift Card you have was intended for use in a country other than your own. Currently, iTunes Gift Cards can only be redeemed in the country where they are purchased.
If the Gift Card was purchased from a third party retailer, you may want to give your Gift Card as a gift to an individual who will be able to redeem it. Apple cannot provide replacements for cards purchased from third party retailers.
Alternatively, if the Gift Card was purchased from Apple, you can have the purchaser contact Apple by using the form at the bottom of this webpage:
http://www.apple.com/support/itunes/store/giftcardI also wanted to let you know that if you would like to purchase from an iTunes Store in a particular country, you must have both a residential address and a billing address in that particular country. Items on any particular country's iTunes Store are available only for distribution to customers who use a credit card, debit card, iTunes Gift Certificate, or iTunes Gift Card issued in and for that country.
For example, the U.K. iTunes Store can only sell to U.K. residents using credit cards or debit cards that were issued in and for the U.K., or U.K. residents using iTunes Gift Certificates or Gift Cards that were purchased in the U.K.
I apologize for any inconvenience this issue may have caused you and hope this information is helpful. If you have any further questions, please don't hesitate to ask. Thank you for your interest in the iTunes Store. We appreciate your business and want your experience with us to be as enjoyable as possible.