If the output from the nokia switchbox is already amplified, I believe you can get speaker to line level converters. A quick look at Crutchfield finds the following: http://www.crutchfield.com/cgi-bin/S-StDqpN8pln5/ProdView.asp?s=0&c=2&g=721&I=101PL2&o=M&a=0, which is the AudioLink PowerLink II Line Output Converter.

Good luck!

-Zeke

just say you weren't paying much attention...