I started looking at dbl.el ,sshell.el and so on with an eye to integrating it into
realgud for debugging gcl.
The copyright in the files hasn't changed from 1998 and is maintained
by William F. Schelter who unfortunately seems to have passed on. And looking from git it looks like indeed the code hasn't changed since around the. But Emacs definitely has.
So are people still using dbl.el and sshell.el?
I asked the same question on the maxima-devel mailing list and the answer I got was that this was unmaintained code.