To me the ultimate portrait lens is a fast f2.8 or better 100 or 105mm prime lens.
For this *istd thing you would need a 66 or a 70mm prime lens, DOES NOT EXIST. That SUCKS. But since 6Mpixel isnt as good as film anyway, you might be able to get away using a zoom at 66-70mm. A 35-105 F3.5 would probably be decent... JCO
