Bit hard to see the polygon edges there I'm affraid, there's just too many of them, but no matter.

Just in case Eric's(EDIT: or Parka's) suggestions didn't do it,

Here's an image of the steps I'd go through to do it.

1) Image just shows the gemetry with a seam
2) All the relevant edges selected
3) With those edges deleted
4) 'Floating' vertices selected
5) Floating vertices deleted
6) Faces to be cut selected
7) After CutFaces tool applied
8) New vertices selected and scaled a teeny bit.

Simon