I am using stunnel as an encryption tool for telnet sessions. access via windows stunnel clients (various versions of stunnel)
is checked by checking for a client certificate (verify=3)

On 18th of July Suse did an patch for libopenssl which upgraded libopenssl0_9_8 (0.9.8j-0.38.1) to libopenssl0_9_8 (0.9.8j-0.44.1)

After this update stunnel 4.36-0.6.1 stopped working, no more tunnels could be opended
Reverting to the previous libopenssl version 0.38.1 cured the error.

I posted the error on the suse support page ( report error ) but until now there was no patch for stunnel or libopenssl

/etc/mcstunnel.config:
client = no
pid = /var/run/stunnel.pid
debug = 7
chroot = /var/lib/stunnel
setuid = stunnel
setgid = nogroup
output = /var/run/stunnel.log
libwrap=yes
verify = 3
CApath = /certs
cert = /etc/stunnel/stunnel.pem
[telnet]
accept = 11111
connect = telnetserver:23