Changes have been made in CVS for this ticket:

Fix name (Bug #8877).
http://cvs.horde.org/diff.php/horde/docs/CHANGES?rt=horde&r1=1.515.2.630&r2=1.515.2.631&ty=u

Lol .. just figured out you put me in the changelog. Thanks a lot.

But maybe you want to put my correct name there:
Sebastian Rettenberger

Changes have been made in Git for this ticket:

MFB: Allow to update existing identities while requiring email 
confirmation (Sebastian Radish, Bug #8877).

http://git.horde.org/diff.php/framework/Prefs/lib/Horde/Prefs/Identity.php?rt=horde-git&r1=cd624150e5fa2d0f3aa6edcc966d7d588f14a1c9&r2=62b5bb50dca647fc9eea5d6bfbfc43f597574eb8
http://git.horde.org/diff.php/horde/docs/CHANGES?rt=horde-git&r1=6c1bfbb2741e6788db1c8acdfe41e42d0830f212&r2=62b5bb50dca647fc9eea5d6bfbfc43f597574eb8

Tweaked and committed, thanks!

Changes have been made in CVS for this ticket:

Allow to update existing identities while requiring email confirmation 
(Sebastian Radish, Bug #8877).
http://cvs.horde.org/diff.php/framework/Prefs/Attic/Identity.php?rt=horde&r1=1.1.2.13&r2=1.1.2.14&ty=u
http://cvs.horde.org/diff.php/horde/docs/CHANGES?rt=horde&r1=1.515.2.599&r2=1.515.2.600&ty=u

I have configured Horde so users have exactly one identity and they 
need to confirm there mail address if they want to change it.

The problem is, that after confirmation the old address stays. The 
problem is, that if someone confirms an address the address is ALWAYS 
added as a new identity. I think this is not wanted for multiple 
identities either.

I have written a patch that works for me, but it would probably better 
if someone has a look at it and maybe make it official:
------------------------------------
--- a/horde/lib/Horde/Identity.php      2009-04-30 17:34:28.000000000 +0000
+++ b/horde/lib/Horde/Identity.php      2009-08-02 20:06:56.000000000 +0000
@@ -467,13 +467,18 @@
                  return array(_("Email addresses to confirm not 
found."), 'horde.message');
              } else {
                  $identity = 
$this->_prefs->convertFromDriver($confirm[$hash], NLS::getCharset());
-                $verified = array();
-                foreach ($identity as $key => $value) {
-                    if (!$this->_prefs->isLocked($key)) {
-                        $verified[$key] = $value;
-                    }
-                }
-                $this->add($verified);
+               $id = array_search($identity['id'], $this->getAll('id'));
+               if ($id !== false) {
+                   $this->setValue('from_addr', $identity['from_addr'], $id);
+               } else {
+                    $verified = array();
+                    foreach ($identity as $key => $value) {
+                        if (!$this->_prefs->isLocked($key)) {
+                            $verified[$key] = $value;
+                        }
+                     }
+                     $this->add($verified);
+               }
                  $this->save();
                  unset($confirm[$hash]);
                  $this->_prefs->setValue('confirm_email', 
serialize($confirm), false);