The ChangeLog entry:

Version 4.28, 2009.11.08, urgency: MEDIUM:
* New features
 - Win32 DLLs for OpenSSL 0.9.8l.
 - Transparent proxy support on Linux kernels >=2.6.28.
   See the manual for details.
 - New socket options to control TCP keepalive on Linux:
   TCP_KEEPCNT, TCP_KEEPIDLE, TCP_KEEPINTVL.
 - SSL options updated for the recent version of OpenSSL library.
* Bugfixes
 - A serious bug in asynchronous shutdown code fixed.
 - Data alignment updated in libwrap.c.
 - Polish manual encoding fixed.
 - Notes on compression implementation in OpenSSL added to the manual.

SHA-1 value for stunnel-4.28.tar.gz:
868cba9ec56ed6a02c8ecfa2a87614b4d433611b

Home page: http://stunnel.mirt.net/
Download: ftp://stunnel.mirt.net/stunnel/

Best regards,
Michal Trojnara