I have a 8GB SD in external slot of my N800. Navicore map somehow hard-coded /media/mmc2/maps to store its maps and POI data. But I only have about 5MB space in mmc2. So I wan to create a map directory in mmc1 and ln it to mmc2. So I tried to following

/media/mmc2:#ln -s /media/mmc1/maps maps

and I got

ln: ./maps: Operation not permitted

Is this because of both /media/mmc1 and mmc2 are FAT FS? If I can't do this, any one knows how I can let Navicore to store map in /media/mmc1?