UPDATE: Apparently this was old news, or at least in that the Dempster agreed to this awhile back according to Levine and the money was already used to sign Xavier Nady.
Ryan Dempster has pulled a rather surprising move by agreeing to defer $3M of his salary from this year over the next 3 years at little to no interest. This is according to a Ken Rosenthal tweet. I'm sure we'll get the rest of the story soon enough and see if this was just Dempster's idea or the Cubs approached him because of an impending deal.
Granted deferring $3M when you make $12.5M is like deciding between taking out the Rolls Royce or the Lamborghini for a spin, but it shall never be uttered that Ryan Dempster isn't a team player.