Invalid state passed to moodle_page::set_state in database module

add an instance of database module to a course (as admin, for instance)
be carefull to set Maximum entries = 1
select a student of the course and login as him/her
add the student's first entry using the "Save and add another" button
the form will appear again (because of MDL-24033)
fill the form for the second time
you will get 2 errors:
the first one: the message "You have entered the maximum number of entries allowed!" is displayed before the moodle page header
the last one: in the frame of the page the following message appear: "Coding error detected, it must be fixed by a programmer: Invalid state passed to moodle_page::set_state. We are in state 0 and state 3 was requested."