[support] Trouble with block boxes

Recently converted the d6 db to innodb tables on local, dev and qa platforms. My local box seems to have an issue that the other two do not, though it may have existed prior to the conversion. I hadn't manually created blocks before then, though the site does contain blocks that predate my involvement.

When I add a block, the delta in the blocks table is 0, and the boxes bid is 0. This results in, I believe, the boxes entry not being found when I edit the block, as the title, body and settings are not present. Deleting the block works correctly, and if I manually change the delta to the highest delta for 'block' + 1, and set the bid in boxes to be the same, the issue is gone.

Any thoughts on why I'm ending up with the 0 value?