[Haskell] Fast Packed Strings Question

After a lay off from Haskell for a few months and preparatory to Hac 07, I thought I had better check my laptop was appropriately set up. However, I encountered the following: C:\Documents and Settings\Owner\crypto>Setup build Preprocessing library Crypto-3.1.0... Preprocessing executables for Crypto-3.1.0... Building Crypto-3.1.0... Data/Digest/SHA1.hs:36:17: Could not find module `Data.ByteString': it was found in multiple packages: fps-0.8 base What's the story with fast packed strings these days? Is it now part of base and I shouldn't have installed it? If not, can someone remind me how I hide the module in base? Thanks, Dominic.