ghci history.

Hi all, I've just started learning haskell. I encountered a strange behaviour in ghci. 1. ghci doesn't seem to do pruning of duplicate expressions. If the same expression is entered twice, both of them are stored in the history instead of just one. Bash uses environmental variables (HISTCONTROL and HISTIGNORE ) to modify this behavior. Is there a way to get the same behaviour in ghci? 2. Does the history of ghci get stored somewhere in a file? That would be useful. I'm using ghc-6.8.2 (ubuntu 8.04). Also, is there an updated ghc package (6.8.3) for ubuntu? If not, I'll try to install the binary. Thanks, Venkat.