[Haskell] package with ghc and ghci

Hello, I have some packages for doing signal and image processing stuff. Here is a little test program : \begin{code} module Main where import Hips a = listSignal (1,10) [1..10] b = liftSignals (:+) a a c = fft b main = do putStrLn $ show a putStrLn $ show b putStrLn $ show c \end{code} 1/ Compiled with : ghc -package hips testFFT.hs 2/ interpreted with : ghci-package hips testFFT.h 1/ no problem 2/ dont execute and gives 'unknown package name: =Numeric' (Numeric is another package called by Hips, included in HaskellDSP). Any solution ? Fred