Given a lack of other suggestions here and elsewhere that yielded any progress, I decided to download the current source and attempt to build it on my system.  I didn't see a routine to check for prerequisites being met, so I wound up running ./configure several times and adding the libssl-dev, libwrap0-dev and libsystemd-daemon-dev packages based on what I saw in the output. Perhaps a check routine could be added later?

I then ran make and the output contains neither errors nor warnings, so that looks good.  As suggested in the INSTALL file, I next ran make check and received neither errors nor warnings.

At this point the next step appears to be make install as root, but I am wondering if I should uninstall the stunnel4 package from the repository first.  I am also wondering if I can simply use the existing /etc/stunnel/stunnel.conf that I included in my first post in this thread or if I should start over with one of the examples included with this version.

I would appreciate input from the list on this.  If you want to see further details, such as ./configure or make outputs or configuration files just let me know and I will put them in a follow-up post.