For those interested: Using MapSource under Linux is very well possible ... including the fully operational data transfer via the USB port
Since I wanted to try out virtualization for quite a while, a recent thread in the German NaviBoard forum
triggered my curiosity. In a nutshell: It took me about one evening (this includes installing MS Windows XP and MapSource in the virtual machine), then I could use MapSource and connect to the GPSr.
I have put a relatively detailed description on my homepage
. Please note that this covers Fedora 8
only - installation notes for Ubuntu can be found in the thread above, and the necessary steps for other distros can probably be derived from the description there
(... anyway, the key difference is the activation of the access to the USB filesystem).