stunnel4 start fails on single node

root@resettest:~# /etc/init.d/stunnel4 restart
Restarting SSL tunnels: Clients allowed=2000
stunnel 4.53 on x86_64-pc-linux-gnu platform
Compiled/running with OpenSSL 1.0.1e 11 Feb 2013
Threading:PTHREAD SSL:+ENGINE+OCSP Auth:LIBWRAP Sockets:POLL+IPv6
Reading configuration from file /etc/stunnel/couch_server.conf
Compression not enabled
PRNG seeded successfully
Initializing service section [couch_server]
/etc/x509/keys/leap_couchdb.key: No such file or directory (2)
str_stats: 14 block(s), 1148 data byte(s), 812 control byte(s)
[Failed: /etc/stunnel/couch_server.conf]
You should check that you have specified the pid= in you configuration file

(from redmine: created on 2013-09-09, closed on 2013-09-13)