Just splash out and get a CF tripod. They are so much lighter than any Aluminium.
I'm using a Manfrotto 055cxpro3 which is pretty awesome. The heaviest setup I've used on it is an EOS1N + 70-200 2.8 IS II. The head is a 488 RC2 which is also very sturdy but I've subsequently discovered the RC4 heads are more highly regarded among many, in the know.
The whole setup is lighter than my old 190 Aluminium tripod with a 3 way head. It is quite large though so I am currently in the market for something that is more compact for traveling and when not using such heavy gear.