Torrents vanish when disc space full

[Manabyrn]

Transmission version: 1.51 (7958)
MacOS X 10.5.6

Sometimes, on start-up, the list of active torrents would suddenly be empty. The recipe (afaict):
Fill up hard disc until MacOS dialogue "Your start-up disc is almost full" appears.
Run Transmission and create some free disc space by removing some of the finished (seeding) torrents
Close Transmission
Subsequent run of Transmission reveals an empty transfer record.

This happened a couple of times before (on previous versions of Transmission as well), but I've only confirmed suspicions this time round. The completed files are still in tact in moved the correct folder. The active files remain where they should as well. It's as if the torrent files themselves have vanished.

[essiw]

they go to paused mode

[Manabyrn]

they go to paused mode

I may have been unclear. The transfer lists are all empty, not merely paused. The only way to get them back is to re-download the original torrent file. Transmission does recognize the partial file and carries on where left off, however.

Note that the transfers only vanish on the subsequent run off Transmission.app - while there's no disc space available, the transfers are all in tact.