problems building trhsx-0.2 with ghc-6.5.20050723

I built and installed ghc-6.5.20050723 on Linux from sources successfully, and it looks quite normally-working. I've stepped into a problem building trhsx from a package haskell-src-exts-0.2.tar.gz with a quite unexpected (for me) message: Preprocessing executables for trhsx-0.2... Building trhsx-0.2... hsSourceDirs: ["."] Chasing modules from: Hsx.hs Hsx.hs:6:7: Could not find module `Data.List': it is a member of package base-1.0, which is hidden Lines in error is quite innocent-looking: import Data.List (intersperse, isPrefixOf) GHC version 6.4 builds that module okay. Is that error is due to beta version of ghc-6.5.20050723, or I am misunderstanding some configuration issues? TIA, Vadim.