Apparently all the parties involved have to do is cross the t's and dot the...lower case j's. Link
Oswalt hasn't officially waived his no-trade clause to OK the deal, the source said. But after considering his options and speaking with friends familiar with the Phillies' situation, the source said the Houston Astros' staff ace is prepared to go to Philadelphia.
The only question on the table right now is the return the Astros will get for Oswalt. Reportedly, they will be paying $11m of Oswalt's deal. The rumored return is Happ, Gose, and Worley, but there have been reports that Singleton might be involved.