Dissapearing buckets in furnaces

Recently, on our self-hosted server, we changed our main source of furnace fuel to lava. But now we have encountered the following problem.

When a bucket of lava is used in a furnace, as fuel, it becomes empty.
But it stays in the furnace and will dissapear like dropped items.
Even when a hopper is placed underneath, it will still dissapear.

This is an obnoxius problem that could be solved easily
e.g. a hopper detects the empty bucket and automaticly extracts said bucket, like a bucket can be placed in a furnace with a hopper.

We would be delighted if you could encompass this little improvement in oncoming snapshot.

-Krifl