[Xastir] maps directory question

[VK5ZTY]

On the aprs sig the question about a linux live CD with xastir and other
amateur radio programs was asked.

A local amateur has tried a knoppix distro from
 http://www.afu-knoppix.de/ 

The copy he has is largely in german, but that can be worked around with
the LANG variable and xastir with the -l switch.

The next problem is maps.  There are some maps on the CD but not for
this part of the world.

Is there any way to specify an alternative maps directory on startup so
that xastir looks for maps on the hard drive instead of on the CD.

Thanks

John
VK5ZTY