It would also be nice to have a dummy-GPS mode, where you could put the longtitude/latitude as a command line argument for gsmmap.
I think most people won't move much debugging with osmocon, so a static position is sufficient.
But: there is already an application for GPSd, gpsfake which can fake positions (and can give a static position). If full GPSd-compatibility is made, this would be redundant.