I am running GPSdrive as a user and am having problems with setting permissions of the serial ports, FC4.

Log in as root, set permissions to allow all users access, then switch to user account. Works fine.

Reboot computer, and the permissions set in previous session are gone.

What's the deal here? Thought if you set the port permissions, they would remain, what am I missing here?

What directory did you go to as root to set your permissions?

/dev

Pref TTYS0, set "Others"

Going by my Mandrake 9.0 (your FC4 should be the similar or the same since it is a descendant of Red Hat 9, a cousin of Mandrake 9) /dev/ttyS0's permissions show as: owner = <logged-in user>; group = tty; everyone-else = no permissions.

This suggests that making serial ports available for a user is one of the things that a login script in one of these distributions does when you log in as a regular user, but, for some reason that isn't being done with the serial port you are using.

What kind of serial port is it: built in to your motherboard; serial port card; or internal modem?