Look for this section in inittab:
Code:
# These are the standard console login getties in multiuser mode:
c1:12345:respawn:/sbin/agetty 38400 tty1 linux
c2:12345:respawn:/sbin/agetty 38400 tty2 linux
c3:12345:respawn:/sbin/agetty 38400 tty3 linux
c4:12345:respawn:/sbin/agetty 38400 tty4 linux
c5:12345:respawn:/sbin/agetty 38400 tty5 linux
c6:12345:respawn:/sbin/agetty 38400 tty6 linux
Make sure that 4 is listed after the c1-c6 segment on each line. The default install leaves runlevel 4 without access to all tty's.
HTH