http://drupal.org/node/11517. I have done this using some command line magic:

find . -name README -exec cp '{}' '{}.txt' \; -exec cvs remove -f '{}' \; -exec cvs add '{}.txt' \;

I will update all occurences of 'README' to 'README.txt' in the conrtib CVS,
soon. I'll also rename LICENSE, CHANGELOG etc. files as soon as I get around
to it.

Add optional 'write to author' links for nodes/comments (modified patch by jik)
other minor code updates/cleanup

- Theme system updates: theme() function return their data now.

Patch by Craig Courtney (thanks!)

- updated to latest cvs, should work in Drupal 4.2
- added folders, you can move messages in folders, empty folders
- mail once per day if you have unread messages (user option)
- message pruning (move old messages to another table)
- list of contacts: it's built automatically looking at users you write to
- theme()ized
- if you are updating run you just need to run privatemsg.sql

- Updated the private message module to CVS.  Patch by John Cappiello.

  'theme("function")' instead of '$theme->function()'.  Hopefully I didn't
  break anything.  If I did, let me know.

  The following modules need special attention (but should still work as is):

  1. The ldap_integration directory has its own user.module; I haven't updated
     the documentation bit that talks about themes.

  2. The hotlist module uses '$theme->hotlist_del_icon'.  Should be avoided
     and somehow wrapped in a (larger) call to theme().

  3. The image module has its own way of doing what 'theme()' does (or the
     former 'theme_invoke()').  Constructs like the one below (a) look wrong
     and (b) should be rewritten to properly use 'theme()'.  For example:

     $theme->box("foo", method_exists("bar") ? $theme->bar() : $bar);

     Search for "image_gallery_album", "image_gallery_home" and
     "image_thumb_browser".  I've already changed '$theme->box()' to
     'theme()'.

  4. The sidebar module uses '$theme->foreground' and '$theme->background'.
     Should be avoided and somehow wrapped in a (larger) call to theme().

  5. The org_informations module uses '$theme->separator()', which is new to
     me.

  6. The taxonomy_filter module uses '$theme->taxolist_filter_item()'.  It
     should use 'theme("taxolist_filter_item")' instead.  I haven't changed
     it because it would probably fail to resolve the default function if
     not overridden by a theme.

  7. The taxonomy_dhtml module's INSTALL file still talks about
     '$theme->image'.

  8. The xloadtree module's INSTALL file still talks about '$theme->image'.

  9. I haven't updated the style.module; too many $theme's, though I don't
     think it needs any updates.

  [I'll try to update the sandboxes later on.]

- See http://lists.drupal.org/pipermail/drupal-devel/2003-February/021824.html.

- used t() and l() and new db_query() syntax everywhere
- minor bugs fixed

----------------
- moved link to private messages to the user block.
- added link to send messages to user info pages.
- some XHTML changes.
- user system has changed from $user->id to $user->uid.

- messages splitted in pages, setting for "how many messages per page"
- privatemsg_get_link() to add theme support; see INSTALL
- throttle to limit abuse; setting in admin for max send rate
- checked sql indexing and added index to recipient
- save sender ip address
- code cleanup (less global variables, use drupal form functions, better date format in list, comply to coding standards)
- minor cosmetic changes