I'm designing a MIDI project using these SDS-50J connectors. The datasheet provides a suggested footprint diagram and labels the pins 1 through 5:
It does not, however, label the bottom-most two pins circled in red. Should I assume that these pins are for mounting only and should be left unconnected, or are they shield pins to be grounded on one end?
EDIT: You can see this pins on the photo, too:
Also, this table on page 2 of the datasheet may provide a clue: