So, uh, wasn’t Dell (DELL) supposed to be working on a cell phone? Well, that was the scuttlebutt. But Dell has failed to show at recent mobile trade shows. Shaw Wu, an analyst at Kaufman Bros. , asserts in a research note today that the company’s first attempt was basically rejected by the carriers as too, well, Dell-like . He asserts that Dell showed a prototype to the carriers, but that they weren’t all that impressed. “From our conversation with supply chain ...