[ubuntu-uk] Firefox3 on network

[Mac]

Friends >>> I'd be glad of any thoughts you can offer on this, as I've 
run out of ideas...

I currently use Ubuntu 7.10 on two or three machines, each with Firefox 
2, which all use the same bookmarks stored on a FAT32 network drive.

I plan to upgrade to Ubuntu 8.04 + Firefox 3, and want all my machines 
to share the bookmarks via the LAN. But the only way to do this with FF3 
is to have all the machines use the same profile, stored on the LAN. 
(This is something I already do successfully with Thunderbird, to access 
my mail from any machine.  I'm aware that only one machine at a time 
should be using the common profile.)

I've been experimenting with a single 8.04 machine running FF3. 
Bookmarks work properly if the profile is on the machine itself.  When I 
move the profile to the network drive, FF3 appears to run OK, but I 
cannot add, delete or organise bookmarks - which rather defeats the 
whole object!

Despite long searches on the net, I can't work out why FF3 does not to 
let me modify bookmarks with the networked set up.  Any ideas?  Has 
anyone solved the problem of sharing FF3 bookmarks over a LAN in this or 
some other way?

TIA

Mac