Issues changing the language of my CS6 Production Premium

Hello, the last september the studio I work for has bought 8 (eight) CS6 Production Premium Suite.

Due to some urgent deadlines and some works in progress we had to wait until the last Christmas holydays to install and set up all the new hardwares and softwares.

We started to install them and only today we realized that seems impossible to change the language from italian to english.

Since here everyone has always worked with the english versions of the Adobe softwares,

since we all follow tutorials, use plug-ins and work with other people from abroad

and since our common language is the english,

it is absolutely impossible for us to work with the italian versions.

We tried to switch to english using this "rename method"

http://www.youtube.com/watch?v=osshLLrXEq4

but didn't work, as at the reboot it was saying that our serial was only valid for an "italian" version of the software.

Then we called the italian Adobe customer care, and they said that the 8 (eight) licenses we bought were "italian" license so it is "normal" that we can't switch language,

and to do so we have to buy a new "english" license.

We are asking if anyone can call this "a solution" considering we have already spent more than 15.000 euros (more than 20.000 dollars)!

You can imagine how we felt: designer, editors, motion-graphers with 10-15 years of experience, always using daily Adobe softwares in english.

At the moment we don't want to believe that it is so difficult to set a language of a software, that it is requested to buy it again.

We hope you can provide any help to solve this situation.

Thank you very much.