How to use non-standard imap port?

[Nikolaus Rath <Nikolaus@rath.org>]

Hello,

I'd like to connect to a non-standard IMAP port (8421). I've added a
(nnimap-server-port "8421") entry to my nnimap entry in
gnus-secondary-select methods.

However, when I attempt to start Gnus the connection to the imap server
fails with

| Warning: Unable to open server nnimap due to: Wrong type argument: stringp, nil

I've tried to set nnimap-server-port to 8214 (instead of "8421")
instead, but that did not work either.

I've enabled "Enter Debugger on Error", but for some reason the debugger
is not actually entered (I assume Gnus somehow catches the error?).

I've also single stepped through the nnimap-open-connection-1 function,
but it runs just fine, so the error is happening at some later point.


Does anyone have a suggestion what I can do to find out where the
problem is?


Best,
-Nikolaus

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