Comment 87 for bug 61463

This just bit me too. One of the xen-tools shell scripts does an "rm tty[^1]", to remove all ttys except tty1, which works in bash, but in dash the result is the opposite: tty1 is removed, and none of the others are.
This silent mis-behaviour then later means you cannot log into your newly-created server later, and you waste lots of time.

Yes, I have reported this upstream, and yes, I'll run "sudo dpkg-reconfigure dash -- No!" on my systems. But I find it ridiculous that Ubuntu is placing its users in this position.