It looks like you would need to add the experimental version from
sid.
But you don't need Bitcoin-QT to mine.
You could install any miner program e.g.
bfgminer and point it to a mining pool e.g.
Eligius.
I would recommend you install
Electrum.
It's a easy and fast client with no need for the initial blockchain download.
And it has deterministic address generation from a seed.