Parsing of lambdas is not consistent with Haskell'98 report.
Consider the following expression:
(\x -> x :: Int . id)
GHC (without any -X flags) currently reports a parse error:
.' in typeInt . id'[[br]] Use -XTypeOperators to allow operators in types
However, I think this expression is legal in Haskell'98 (and indeed still legal in Haskell 2010). The report gives an (ambiguous) expression grammar, which (unambiguously) parses the above as (\x -> (x :: Int)) . id. The report further says that lambdas extend as far as possible to the right, but the parse which GHC is using is not a possible parse according to the grammar, since infix operators (other than "->") are not allowed in the construction 'type'.
That said, I'd much rather see this fixed in the Haskell 2011 report than in GHC :)