Forum Moderators: mack
your first path should probably be a fully qualified url or at least a root relative path (have a starting slash). I would try a fully qualified url first.
I have also never used the code I always use permanent
Redirect permanent http://www.example.com/mysite/dirctory/subdirectory/mypage.html http://www.example.com/directory/index.php
or with a starting slash
Redirect permanent /mysite/dirctory/subdirectory/mypage.html http://www.example.com/directory/index.php