User profiles

I use Firefox and Thunderbird under EXP and plan to use them under Kubuntu.

I would like to use the same profile directories under both OS's

Under Kubuntu is it possible to  direct these programs to the profiles I 
use under EXP (Kubuntu can already read and write to the FAT32 
partitions).  I tried to change the default directory locations under XP 
with no success.
Thanks
Preston