[Haskell-cafe] Build dependency problem with bytestring.

Hi all, I'm upgrading HAppS from my 0.9.2 to the current 0.9.2.1 in Hackage. Some HAppS components have built and installed (IxSet and Util). Halfway through the HAppS-State build, the GHC runtime linker gives a fatal error on finding a duplicate definition for symbol fps_minimum while loading bytestring 0.9.0.4 after having already loaded bytestring 0.9.0.1. From trial and error, I'm guessing that HAppS-State needs 0.9.0.1 but one of its build dependencies was built with 0.9.0.4. Using GHC 6.8.2 Linux here. Any suggestions on how best to currently approach this situation? Thanks, Jon