haskell - Could not find module, it is a member of the hidden package haskell98 -

when try compile simple source file import io or import random, build fails error message this:

could not find module 'io' member of hidden package 'haskell98-2.0.0.1' use -v see list of files searched 

the module names changed @ point. want import system.io , import system.random instead.

here module hierarchy standard libraries in ghc 7.6.1.