Change group of realport ports at startup (Fedora 10)

I have a Portserver8 running with realport software under F10. But the ports are in group root. I would like to change the group to uucp to match the regular ports and allow users in uucp group to access. I can do this with
chgrp uucp /dev/ttyaa00
and similar for other ports. But want this done automatically at startup for run levels 3 and 5 (at least). I tried adding the chgrp commands to the end of /etc/rc.d/rc.local because this is said to be the last startup script to run. But the log says
chgrp: cannot access ‘/dev/ttyaa00’: no such file or directory

How can I do this?

Based on this thread:,4407#13674

I added a GROUP declaration to the end of the first line in /etc/udev/rules.d/10-dgrp.rules to get:
KERNEL==“tty_dgrp*”, PROGRAM=“/usr/bin/dgrp_udev %k”, NAME=“%c”, GROUP=“uucp”

Problem solved. Maybe this will help someone else…