[Add -ignore-package lang to fix building with GHC 6.4
Einar Karttunen <ekarttun@cs.helsinki.fi>**20050915144532] hunk ./Makefile 7
-GHCOPTS=   -O   -pgmF drift-ghc  -F $(GHCDEBUGOPTS) $(GHCINC) $(PACKAGES) -fwarn-type-defaults   -fallow-undecidable-instances  -fglasgow-exts -fallow-overlapping-instances
+GHCOPTS=   -O -ignore-package lang  -pgmF drift-ghc  -F $(GHCDEBUGOPTS) $(GHCINC) $(PACKAGES) -fwarn-type-defaults   -fallow-undecidable-instances  -fglasgow-exts -fallow-overlapping-instances