Meteor blasters not being refilled, either by duplicants or auto-sweepers (ADDITION: refills only when completely empty)

UPDATE/ADDITIONAL INFO: The meteor blaster's refill errand only becomes active once the meteor blaster is completely empty.

(UPDATE 2: This one is a "Doh" update - I only now noticed there is a conveyor rail input on the meteor blasters. But the bug report is still valid so I'll leave it up.)

Dupes fill meteor blasters with blastshot when the meteor blaster is built. After that I can't get them to refill them. The same goes for auto-sweepers.

The picture is of an auto-sweeper in range of a meteor blaster that is less than full and a conveyor receptacle with blastshot.