Unlock DVD

Hi!
I am a newbie and this is my first post. I searched all over the net for my problem with no luck. I own a MB E500 2003. I want to:
1. Unlock the DVD to play all regions
2. Enable the MP3 playing capability.
 
I tried the key sequence and managed to ge to the engineering screen, but failed  to go beyond it (using *   +   #   +  <). Can anybody help me pleaes? I live in Dubai/UAE and the specs of the car is GCC.
 
I would like also to know where i can buy a navigation DVD for GCC. The dealer here sells it for an outregious price (around US$ 1,200) .
 
Thanks in advance

post over on    http://www.mbworld.org/forums/index.php
in the w211 section and in the audio section.
Someone also had a nav dvd for sale cheap.
You may also want to ask  on w211   http://www.benzworld.org/forums/
http://www.benzworld.org/forums/w211-e-class/
and the audio section

I wish you luck,
ohlord