Does Jack Straw want to be the next leader of the labour party?

I just wondered as the BBC report that:

"Jack Straw is to amend plans allowing life peers to resign from the House of Lords, to stop them standing as an MP for up to five years, it is reported.

The FT reports the justice secretary wants a "cooling off" period inserted into the Constitutional Reform Bill. "

Now I know that Peter Mandelson was reported as saying that he saw

"no prospect... of standing as leader of the Labour Party....A peerage is for life. A life peerage is a life peerage.... "It is me officially ruling it out"

But as I blogged at the time

"The odd thing is I think he may have still left himself a get out; at present he is correct to say "There is no opportunity for me to divest myself of my life peerage. A peerage is for life. A life peerage is a life peerage" but once that barrier is lifted could he say that now the law has changed and because the Labour party and the Country needs him..."

So is this Jack Straw making sure that Peter Mandelson is definitely out of the running to be the next Labour leader? And if so on his own behalf or for someone else?