In Prelude support

Polymorphic `seq':

Required by the Haskell 1.3 prelude; not done yet. Consequently, the `strict' function doesn't really do what you want either.

Arbitrary-sized tuples:

Plain old tuples of arbitrary size do work. Note that lots of overloading can give rise to large tuples "under the hood" of your program. HOWEVER: standard instances for tuples (`Eq', `Ord', `Bounded', `Ix' `Read', and `Show') are available only up to 5-tuples. These limitations are easily subvertible, so please ask if you get stuck on them.

Unicode character set:

Haskell 1.4 embraces the Unicode character set, but GHC 2.02 does handle it. Yet.

class `Enum':

In Haskell 1.4, `Ord' is dropped as a superclass of `Enum'. GHC 2.02 still has the `Ord' constraint.