Hi,

I have mail-user-agent set to gnus-user-agent, but doing 'C-x m' before
starting Gnus (No Gnus v0.4) gives:

,-----
| Debugger entered--Lisp error: (void-function gnus-agent-possibly-save-gcc)
|   gnus-agent-possibly-save-gcc()
|   run-hooks(message-header-hook)
|   message-send-mail(nil)
|   message-send-via-mail(nil)
|   message-send(nil)
|   message-send-and-exit(nil)
|   call-interactively(message-send-and-exit)
`-----

although no problems occur if Gnus is running or was started once in the
session.

The issue came up in the past, and the best solution I found was:

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