prevent startup imap connection

[Mark Smith]

I am trying to prevent mutt from opening a connection to my imap
spoolfolder on startup. It is simply inconvenient to wait for the
connection each time I start mutt. I have tried "imap_passive", which,
according to the manual, is supposed to prevent imap connections on
startup, but it won't work: an imap connection is opened every time I
open mutt. Does anyone know how to prevent this? I would simply like to
view my cached messages and connect to imap manually if I want to.
Thanks!