LinuxQuestions.org - OpenVPN tunnel problem

I have two servers, both running Red Hat Enterprise Linux AS release 4. I installed the same distro of OpenVPN on both of them. Both servers config files are the same. However, on the one OpenVPN is up and running without any problems. On the other, the tun device is not recognized. The one that is OK looks like this:

Linux distro: Red Hat Enterprise Linux AS release 4 (Nahant)

OpenVPN distro: openvpn-2.0.2-1.1.fc3.rf

Kernel: 2.6.9-5.EL i686

[root@fw1 dev]# grep TUN /boot/config-2.6.9-5.EL
CONFIG_INET_TUNNEL=m
CONFIG_INET6_TUNNEL=m
CONFIG_IPV6_TUNNEL=m
CONFIG_TUN=m
# CONFIG_8139TOO_TUNE_TWISTER is not set
# CONFIG_ATM_ENI_TUNE_BURST is not set
# CONFIG_TUNER_3036 is not set

[root@fw1 dev]# cd /dev/net
[root@fw1 net]# ls -l
total 0
crw------- 1 root root 10, 200 Feb 24 13:35 tun

The one that does not want to come up looks like this:

Linux distro: Red Hat Enterprise Linux AS release 4 (Nahant Update 2)

OpenVPN distro: openvpn-2.0.2-1.1.fc3.rf

Kernel: 2.6.9-22.0.1.ELsmp x86_64

[root@localhost ~]# grep TUN /boot/config-2.6.9-22.0.1.EL
CONFIG_INET_TUNNEL=m
CONFIG_INET6_TUNNEL=m
CONFIG_IPV6_TUNNEL=m
CONFIG_TUN=m
# CONFIG_8139TOO_TUNE_TWISTER is not set
# CONFIG_ATM_ENI_TUNE_BURST is not set
# CONFIG_TUNER_3036 is not set

[root@localhost ~]# cd /dev/net/
[root@localhost net]# ls -l
total 0
crw------- 1 root root 10, 200 Mar 4 09:25 tun

The error is:
[root@localhost ~]# openvpn --config /etc/openvpn/server.conf
Sat Mar 4 10:46:03 2006 OpenVPN 2.0.2 i386-redhat-linux [SSL] [LZO] [EPOLL] built on Sep 8 2005
Sat Mar 4 10:46:03 2006 Diffie-Hellman initialized with 1024 bit key
Sat Mar 4 10:46:03 2006 TLS-Auth MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ]
Sat Mar 4 10:46:03 2006 TUN/TAP device opened
Sat Mar 4 10:46:03 2006 Note: Cannot set tx queue length on : No such device (errno=19)
Sat Mar 4 10:46:03 2006 /sbin/ip link set dev up mtu 1500
SIOCSIFMTU: No such device
Sat Mar 4 10:46:03 2006 Linux ip link set failed: shell command exited with error status: 255
Sat Mar 4 10:46:03 2006 Exiting

There is a space where the device name should be. I have tried numerous times, but nothing. Anyone have an idea how to fix this?