Why do these error occur? After hiding the packages com (beeing in comlib) and hdirect (beeing in lib) and adding -package com -package hdirect it works fine. I haven't tried without hiding but adding -package options yet. ghc --make -H16m -O -fglasgow-exts -syslib com -fno-warn-missing-methods daotest.hs Chasing modules from: daotest.hs Skipping DAO ( ./DAO.hs, ./DAO.o ) Skipping DB ( ./DB.hs, ./DB.o ) Skipping Main ( daotest.hs, daotest.o ) Linking ... c:\haskell\myfptoolsdirectory\fptools\hdirect\comlib/libHScom.a(PointerPrim.o)(.text+0x696):ghc2648.hc: multiple definition of `__stginit_PointerPrim_' c:\haskell\myfptoolsdirectory\fptools\hdirect\lib/libHShdirect.a(PointerPrim__12.o)(.text+0x0):ghc2036.hc: first defined here c:\haskell\myfptoolsdirectory\fptools\hdirect\comlib/libHScom.a(PointerPrim.o)(.text+0x6da):ghc2648.hc: multiple definition of `__stginit_PointerPrim' c:\haskell\myfptoolsdirectory\fptools\hdirect\lib/libHShdirect.a(PointerPrim__12.o)(.text+0x44):ghc2036.hc: first defined here Marc