Then that probably suggests you did not enable the serial service when you installed VL. do this:
1) dmesg | grep serial
you should see something like this:
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
that means the kernel sees your serial ports and they are probably functioning from a hardware perspective.
2) ls -al /etc/rc.d
you should see this:
-rwxr-xr-x 1 root root 2895 2006-10-18 23:38 /etc/rc.d/rc.serial*
If there are no "x"'s then you have not enable the serial service and you need to go to VASM, SUPER, HARDWARE, HWSET and enable serial.