[stunnel-users] stunnel4 with exec as service for securing pop3

I would like to run the stunnel4 daemon in order to provide a pop3s service by using a pop server (solid-pop3d). The following configuration file doesn't work (the pop3 server doesn't start, I think) and I would like to ask for any hints.

--stunnel.conf>>>

cert = /etc/stunnel/stunnel4.pem

sslVersion = SSLv3

[pop3s] accept = 995 exec = /usr/sbin/solid-pop3d execargs = solid-pop3d

<<<stunnel.conf--

I would expect stunnel4 to start up solid-pop3d every time someone connects to port 995 and communicate to solid-pop3d, just like inetd would do, if configured to serve solid-pop3d.

By the way, I have opened the service "pop3s" in /etc/hosts.allow.

Thanks in advance for any help.