The story goes that the Pirates initiated a potential deal with the Phillies, seeing that Brandon Duckworth has struggled and that the Phillies might want some start in the pitching rotation. The Pirates were drawn to Philly by the strength of the Phillies minor league system.
If Pittsburgh has their way, they would walk away with Ryan Madson and Jorge Padilla for Suppan. The Phillies reportedly won't consider including Madson in a deal for a pitcher of Suppan's caliber, so it's unlikely that deal would work from the Phillies side of things. The Phillies responded with a possible offer of Keith Bucktrot and Eric Valent, which the Pirates didn't immediately reject.
The Phillies would prefer not to part with Madson or Bucktrot in the deal, but unless the Pirates panic as the deadline nears, it's likely that they're going to have to give up one of the young pitchers. The Phillies would prefer to send Valent to Pittsburgh instead of Padilla, but they would include Padilla as part of the package to make things work. The Phillies have also asked the Pirates if they might want Duckworth as part of the deal. The Pirates favor Madson because he is closer to being able to pitch in the majors.
Actually, the Phillies are divided over making a deal for another starting pitcher. Pitching coach Joe Kerrigan has made Duckworth into his private project and many in the organization believe Duckworth simply needs to build some strength and will be an above average major league pitcher. Others in the organization feel that Duckworth won't be anything more than a journeyman type pitcher and that if they can get Suppan or another somewhat established pitcher in exchange for the young right-hander, it would be well worth it.
The Phillies have long admired Baltimore's Sydney Ponson and Jason Johnson, but the asking price for Ponson is likely to be too high and the Orioles likely won't deal Johnson. The Phillies also asked the Mets in passing, about Steve Trachsel. Higher profile pitchers such as Kelvim Escobar of Toronto are out of the Phillies price range in terms of the players that the Phillies would have to sacrifice in the deal.