Hi
Does the cradle have a curly cord, or is it fixed in place. If its curly, the system is a fixed Nokia 6310i system. You can add a device called a ViseeO that gives you bluetooth for using with a new phone. They are at
www.comandonline.co.uk (along with other bluetooth solutions etc) and there's a voucher code for a discount on ViseeO in a recent thread here, valid till the end of the month.
If its fixed in place, you have UHI, which means the cradle can be slid off backwards when you press the little button near the top on the surface. The next question then is, is it a mid 04 facelift car, or before. If you look at the stereo, if there is metal/wood visible the whole way round, then it is before, if the unit occupies full width of the centre console it is facelift.
If it is facelift, you can use either of the mercedes bluetooth HFP or SAP cradles - depending on what phone you have.
If it is pre-facelift, you have to use the SAP cradle, or a 6310i cradle + ViseeO.
Hope that explains
R
*edit, discount thread is
http://www.mbclub.co.uk/forums/showthread.php?t=46021 )