There is a tracker for bugs and feature requests: http://hackage.haskell.org/trac/c2hs/. Alternatively if you prefer email please send your bug reports and suggestions to the C->Haskell List <c2hs@haskell.org>.

A good bug report contains information on the used operating system and Haskell compiler as well as the version of C➔Haskell that you have been using. You can obtain the version information by running c2hs --version. If possible a concise example illustrating your problem would be appreciated.