Possibly ancient history non-compliance.

[Alex Ferguson]

ghc-4.04 and ghc-4.08 both complain about the following:

    No instance for `Show HandlePosn'

But according to the report, they should be showable (if precious
little else).

Haven't a version of 5.00 to hand (but will be installing 5.02,
promise!) so I haven't checked if this has changed since.

Cheers,
Alex.