Thanks.
Updated MM to 2.6.2 and it looks like
bluetooth gps device's mac is hardcoded
as going Settings

Bluetooth entry field is not active, showing mac address of an old
bluetooth device
Scan for GPS is not active

As advised by mardy used
gconftool-2 -a /apps/maemo/maemo-mapper
to set new value of bluetooth GPS device
I can get using general maemo bluetooth Settings

GPS > Select GPS device from list

set new value for GPS receiver_mac read from
the above list
and it didn't work for mm
as it loads old mac address as previously,
so it looks like
mm is reading pair values
from some other default configuration file
I don't know how to access to.

gconftool-2 sits here with man page

http://linux.die.net/man/1/gconftool-2

ok, run gconftool -R
(recursively to get path to mm default configuration file)

and didn't find one.

any help ?

===
MM 2.6.2, 2006He,
MM > Settings > Bluetooth > sits old value
> Scan is disabled

enabling GPS from mm menu > GPS
get
Searching for GPS receiver ......... (after 5 min) ....

btw
BT is set to on in maemo
and I can get maemo connected to remote bluetooth device and paired

mm is searching for GPS receiver another 5 min.