A Halloweeen Ding sale just started, through 10 PM Central Time tonight. Travel is limited to Halloween, so presumably you will need to find another Ding sale for the other half of your trip. See the thread http://www.flyertalk.com/forums/showthread.php?t=611737 or your own copy of Ding.

In other news: The Wright Amendment will shortly be history, allowing two-step routings to and from Dallas Love Field to be booked as regular connecting fares.