Hunter Ellett via tde-users wrote:
I don't know which package has tdeio_smtp but the
Slackbuild seems to
build without this support.
may be it is something slack specific, because here I use KMail for around
10 accounts with authentication.
Why don't you raise this issue in the dev ML?
Or file a bug in TGW?
the tdeio_smtp is part of tdebase (tdeioslave)