I've traced the regression to a specific commit in dovecot. Details at https://dovecot.org/mailman3/archives/list/dove...@dovecot.org/message/LMUX23ZRYPOJ6RRZWBPBUBSBYK4FLI6O/
I'm still not sure exactly how dovecot broke, but I do suspect the fix will have to happen there. So for gsasl (and libgssglue) expect a merge request soon to update their autopkgtests to the dovecot 2.4 configuration language. noah
