Comment 14 for bug 99276

I've just fixed this problem upstream by checking that an UID free before creating the user. If that's not the case, a dialog is shown. This will sadly not be available in GNOME 2.28 because this would imply modifying strings, and that's too late for that.

The bug described in the last comment can be fixed separately and could go into 2.28 if I find how to fix it.