Okay...I was having this exact problem tool...but I figured out a haphazard solution...can't say this is the cleanest solution, but it works!

Here is what I did. You'll need to do this from an xterm probably as root

1) I'm not sure I needed to do this but first thing I did was, but I suggest skipping this step initially:
apt-get upgrade osso-gpsd

2) Next (if you don't know) determine the mac address of your bluetooth gps by running:
hcitool scan

3) cd /etc/bluetooth and edit the rfcomm.conf
configure it similar to the following (not a 100% this actually needs to be done at all):

rfcomm0 {
# Automatically bind the device at startup
bind yes;

# Bluetooth address of the device
device 00:0A:3A:xx:xx:xx; #should be the mac of your bluetooth GPS

# RFCOMM channel for the connection
channel 1;

# Description of the connection
comment "Oncourse";
}

4) from the root shell promt:
rfcomm bind /dev/rfcomm0 00:0A:3A:xx:xx:xx #mac address of your bluetooth

5) next command
/usr/sbin/gpsd -N -n -F /tmp/gps.sock /dev/rfcomm0

You might get a message that pops up asking to pair with you bluetooth GPS.

6) Now run maemo-mapper...everything should start working.

I'm sure there is a cleaner way of doing this, but I haven't had a chance to pursue that further. But I'm able to run the latest version of MM using GPSD Host since my other two options are grayed out and I can't select them. The only pain now is that I have to open an xterm window su to root then run the commands.

Oh well better then nothing...hope this helps some people.