Starting with the 2011-05-05 snapshot, I can't start a shell under emacs. Here are the steps to reproduce:
1. Start emacs in a mintty window.
2. Type<Alt-x>shell<enter>
This yields the following error message in the shell buffer:
sh: cannot set terminal process group (-1): Inappropriate ioctl for device
sh: no job control in this shell
Starting with the 2011-05-28 snapshot, the error message changes to
Process shell aborted
Starting with the 2011-06-01 snapshot, it changes again, this time to
Process shell stopped (tty input)
I still get that error message with the 2011-06-14 snapshot.