Hi, I'm trying to set up a VPN server using OpenVPN and I'm getting some errors while trying to connect the client to the server. I'm getting the following error:

Sun Feb 13 14:54:16 2011 OpenVPN 2.1.4 i686-pc-linux-gnu [SSL] [LZO2] [EPOLL] built on Feb  5 2011
Sun Feb 13 14:54:16 2011 IMPORTANT: OpenVPN's default port number is now 1194, based on an official port number assignment by IANA.  OpenVPN 2.0-beta16 and earlier used 5000 as the default port.
Sun Feb 13 14:54:16 2011 NOTE: OpenVPN 2.1 requires '--script-security 2' or higher to call user-defined scripts or executables
Sun Feb 13 14:54:16 2011 ******* WARNING *******: all encryption and authentication features disabled -- all data will be tunnelled as cleartext
Sun Feb 13 14:54:16 2011 RESOLVE: NOTE: localhost resolves to 2 addresses
Sun Feb 13 14:54:16 2011 Note: Cannot ioctl TUNSETIFF tap0: Device or resource busy (errno=16)
Sun Feb 13 14:54:16 2011 Note: Attempting fallback to kernel 2.2 TUN/TAP interface
Sun Feb 13 14:54:16 2011 Cannot open TUN/TAP dev /dev/tap0: No such file or directory (errno=2)
Sun Feb 13 14:54:16 2011 Exiting

I have bridge-utils installed and tap0 shows up in ifconfig. Can anybody give me a hand? Thanks in advance.