Please see the advice that I gave the previous distressed seller in that other post. First thing I would recommend is to call your lender. It is not hard to do and dealing with the issue is the best thing to do. What sdrealtor said makes alot of sense. One current short sale I have, the second mortgage has been totally wiped out for the cost of $1000 and the first has formally accepted a 60k loss. Both lenders have agreed not to pursue the deficiency. Additionally the sellers had been in default for quite awhile. It has been a royal pain in the rear they are quite relieved. The short sale package was not trivial to fill out. Lenders all vary with the acceptance of a short sale. I would absolutely take everything you read here with a grain of salt. If you want to not talk to your lender that is your prerogative but I would advise you to talk to an attorney if you are going to play cat and mouse with them.
Whether your lender will let you wipe out the second totally or buy it for pennies on the dollar is not known to me but it sure couldn’t help to try.