[Haskell-cafe] Problem linking with GHC 6.8.1

This is a program that works under ghci. GHC was installed using the tarball on hashell.org. When I try to compile the program, it can't link. It used to work with 6.6.1. ghc --version The Glorious Glasgow Haskell Compilation System, version 6.8.1 ghc --make -O2 -o edimail Main.hs [1 of 5] Compiling Decode ( Decode.hs, Decode.o ) [2 of 5] Compiling Net ( Net.hs, Net.o ) [3 of 5] Compiling Smtp ( Smtp.hs, Smtp.o ) [4 of 5] Compiling Pop3 ( Pop3.hs, Pop3.o ) [5 of 5] Compiling Main ( Main.hs, Main.o ) Linking edimail ... /usr/bin/ld: cannot find -lgmp collect2: ld a retourné 1 code d'état d'exécution