When exiting from XFree86 4.2.1, instead of returning to the original tty from which 'startx' was run, you are left on a now blank tty and you have to switch over to the tty from which you came. I hope that was coherent.
Cannot say I have had the problem. What vga card ?
It's an ATI Rage 128 Pro TF, at least according to my XF86Config.
Can you please try 4.2.1-r1 or later ?
No traffic.