OpenStreetMap (plus gpx layer) with Drupal 5.x?

Dear everybody,
I run a website with Drupal 5.x and I am still happy with it (apart from the fact that the trackback module is not working). But now I am at a point, where I can't find a solution for 5.x. I would like to display maps from OpenStreetMap with gpx (or other track) layers on my website. Until now I do this with some modules that use Google maps. I would like to switch to OpenStreetMap because I like OpenSource initiatives. But I only find solutions for 6.x.
Did someone manage the integration of OSM and gpx layers on his website with Drupal 5.x? Or do I really have to step over to 6.x to do this?
I am happy to see your comments. Kind regards - andreas