Use Openstreetmap - Action Sript 3 (AS3) and Show GPS Positions

Hello,

i will show GPS Positions in the Openstreetmap. My problem is: how can i convert the GPS coordinates?
I have only Longitude and Latidude for Example: 48.591115 ,8.509130
And i have not a Flex Projekt. I must develope in AS3 (It´s a part of an existing AS3 Projekt).

Many Thanks for your help!