|As already stated by (macaswell May 9, 2010 at 22:02:01 Pacific)....|
You should tell apache which file it should treat as default when someone attempts to requests a directory(may be home page).
DiectoryIndex is the way to do that. Any file name after "DiectoryIndex" would be opened, if not found the second file should be opened, if that too not found then third.
It would suggest you too secure your . htaccess from accidently being shown also.