[CentOS] Kickstart issue: 'dialog' doesn't work in %post, CentOS 5.5

From: Zhang Huangbin <zhbmaillistonly at gmail.com>
> I use 'chvt 3' in ks file to switch to 3rd tty, but it stays in 1th tty (installation console).
> Swith to 2nd tty with 'Ctrl+Alt+F2', run 'ps' command, i can see dialog process is 
> running.

I fixed it with some execs:

chvt 3
exec < /dev/tty3 > /dev/tty3
/tmp/misc/ks_pre.sh | tee /tmp/ks_pre.log 2>&1
chvt 1
exec < /dev/tty1 > /dev/tty1

JD