I think most people would accept the debt in return for a share of the Great Southern Hotels, Duty-Free business, Birmingham Airport, Hamburg Airport, Dusseldorf Airport etc. It would probably balance nicely ;-)
It seems Dublin Airport wants to retain all Aer Rianta's assets and none of its liabilities.
A long time ago, I said the solution to this was to sell Cork Airport debt-free to an international operator who knows something about running airports. The money could then be used to reduce the debts of the DAA. I stand by that solution, although with the way the international economy has gone, you'd get a much lower price for Cork Airport now than you would have got when I suggested it.