This is from the NEWS file :
* Version 2.6 (released 2011-04-11)
** This release includes lots of patches by members of our open
source community. Thank you all!
** Add Challenge-Response mode for offline validation (requires
YubiKey 2.2). Patch by Tollef Fog Heen.
** Eliminate all problems with pam_get_data by simply getting rid
of that code completely. This seems to have caused problems for a lot
of people.
** Numerous LDAP bug fixes and improvements, including community
patches by judas.iscariote and maxsa...@gmail.com. Change to
LDAPv3, since v2 has been declared historic for a looong time.
** Support passing capath parameter to Yubico validation client.
Patch by Remi Mollon.
** Support public id's longer/shorter than 6 bytes. Patch by
fraser...@gmail.com.
** Convert documentation to Asciidoc format used in Github wiki.
** Try to never log passwords in debug logs.
/Fredrik