Strange behavior of serial port / uucp on FC3 after recent updates

[Michael Carney]

Hi folks,

I've been using uucp for years with no trouble until just recently.
(like within the last week or so). When trying to use the serial port
either to login to the directly attached host (null-modem cable) (via
cu(1) or minicom) or use uucp to copy files between the hosts, I get an
access denied error.

Selinux is disabled (yes I checked /etc/selinux/config).

minicom will work if I run it as root; cu fails regardless of whether
I run it as a user or root. What's really strange is cu(1) will start
working if I strace cu (while running as root):

<startlog>

71> cu -l /dev/ttyS1 -s 115200
cu: /dev/ttyS1: Line in use
72> su
Password:
# cu -l /dev/ttyS1 -s 115200
cu: /dev/ttyS1: Line in use
# strace /usr/bin/cu -l /dev/ttyS1 -s 115200 2> /tmp/foo
# echo $?
0
[ Note: /tmp/foo shows same "Line in use" error]

# strace -f /usr/bin/cu -l /dev/ttyS1 -s 115200 2> /dev/null
Connected.
login: ~[fubar].

Disconnected.
#
# uname -a
Linux fubar 2.6.10-1.766_FC3smp #1 SMP Wed Feb 9 23:21:37 EST 2005 i686
i686i386 GNU/Linux #
</startlog>

What's interesting is cu fails when traced w/o following children,
but succeeds when I trace the child processes (-f). Strange..

Any suggestions?

TIA.