It's an odd call though, certainly as to who makes the concession. If you were to go to see an imam at a mosque, would you respect his wishes and cover your head and remove your shoes, or would you stay as you are and expect him to accept that?
My own feeling is that Straw is making a valid point, but that his timing is crass and opportunistic (given the pending battle for the deputy leadership of the Labour party) and that the right-wing media is going to hijack the issue whatever Straw's personal wishes.