Working visa delay

Hello everyone!

I'm currently planning on moving to Berlin, I'm a Colombian citizen and I live in France since 2011.
I recently graduated from engineering and just found a great job in my domain although the only porblem is that they want me to start as soon as possible (they know I need a working visa).
What I wanted to know is how long (average) does it take for a working visa request take to be accepted (or have an answer) and if there is any possible ways to speed up this process by asking for more documents to my emplyer etc...

It's really a great professional opportunity for me to start my career, so I hope there is a possibility to obtain this permit in less that 6 to 8 weeks (sinca thats the treatment delay that the embassy from France writes in its visa forms :s)

Have a great day everyone!I hope