cant find module PrelPtr

hi i am learning to use green card. when i try to compile the preprocessed haskell file i get the error message ghc-5.04.2: chasing modules from: main.hs ghc-5.04.2: can't find module `PrelPtr' (while processing "/usr/local/lib/green-card/StdDIS.hs") i am using green-card 2.05 and ghc 5.04.2 on freebsd 4.7. what can i do to fix this? chris