`partition'

Dear GHC developers,

the function  let  ns = [1 .. 10^6] :: [Int]
                   p  = partition even ns
              in
              take 2 $ fst p

computes too long in                 ghc-6.2.2-September-26
and needs several megabyte of stack.
What might be the reason?

-----------------
Serge Mechveliani
mechvel@xxxxxxxx