Are you sure you're setting up your repository's "URL Format" correctly? For a WMS-based URL Format to work, it must contain the "SERVICE=WMS" GET parameter somewhere in the URL Format, and it needs the following GET parameter to allow Maemo Mapper to "fill in" the appropriate coordinates: "BBOX=%.6f,%.6f,%.6f,%.6f". Look at the examples in the aforementioned Maemo Mapper Repositories thread for complete examples. (Note that you must copy/paste the linked URLs, since these forums abbreviate the links in the text themselves.)