Can income tax debt be discharged in a bankruptcy?

Answer

Yes.
Suprisingly it is a fairly low (I believe 7th position) claim against the assets.

Answer

Generally speaking, income tax debt can be discharged if the tax was assessed more than three years prior to the filing of the bankruptcy petition. Note that it is from the time the tax was actually assessed against you (generally the date you filed the return). So if you filed your 1999 tax return 5 years late, you'd still have a bit of a wait before that would be dischargeable under bankruptcy.