Since I updated to CF 3.1.1 today the following problem occurs:
If a checkbox is NOT checked, it's name is entered into the generated mail.
[checkbox checkbox-123 "This is a test|TEST"]
should enter "TEST" into the mail if checked and nothing if unchecked. First one is still working fine, but since the update it enters "[checkbox-123]" (with brackets) into the mail if unchecked.