[Exim] dequeueing one message only

hi,

i have a situation here where i need to delay delivery to certain
(remote) addresses. this one is ok so far, messages are nicely held on
the queue. now, i need to dequeue and deliver one of them. only one
particular message, not all messages for the given domain, or for the
given recipient.

how is it done ? i've been playing around with -qf, -d and -M in
variuos combinations, to no success.

this is exim3 here.

thanks for any help,

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