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Aufgegeben von engelchen + in Deutschland Forum
Since you are using Google translate anyway, I will just answer in English. : )
I have said this before, there is really no point in trying to change careers now. Yes, there are not enough experienced engineers. However, there are more than enough engineering graduates. Most companies in Germany are not interested in engineers without experience. If you can't find a job in Germany with an MBA and experience, you surely won't be able to find a job as an engineer without experience.
On top of which, without German it will be difficult to make enough just to support yourself while studying, there is no way you will be able to support a family as well and keep up with your studies. I know enough foreign students struggling to support themselves and finish their studies.
The first thing you need to do is apply for and obtain your Polish passport; with it you can work in London, Zurich, and (as of May, 1, 2011) Frankfurt without needing a work visa. You can try contacting headhunters to see if they would be interested in someone with your profile. If not, plan a trip to one of the cities and mention when you are going to be there in your cover letters.
You might also keep in mind that workers are not interchangeable. Yes, there will probably be many Eastern European citizens who will be trying to find unskilled work in Germany from May. The market is already flooded. You need to concentrate on the market segments in which you have experience.
Good luck!