Well,

it works now.

Turns out the problem was starting with the wrong .mc file in
/usr/share/sendmail/cf

The "zhadum.mc" file was closest to my config, and, with changing a few lines,
sendmail was back listening to port 25:

$ netstat -f inet -a
Active Internet connections (including servers)
Proto Recv-Q Send-Q  Local Address          Foreign Address        State
tcp        0      0  *.587                  *.*                    LISTEN
tcp        0      0  *.smtp                 *.*                    LISTEN
tcp        0      0  *.discard              *.*                    LISTEN
tcp        0      0  *.echo                 *.*                    LISTEN
tcp        0      0  *.ssh                  *.*                    LISTEN
udp        0      0  *.discard              *.* 
udp        0      0  *.echo                 *.*


Thanks all for the help!


-Mike