[exim] only queue certain domains

Hi List,

I've setup following line in exim 4.63 config:

queue_domains = !mydomain.tld : *

queue_only is _not_ set

What I'm expecting exim to do is:
put all arriving mails in the queue, except for the domain mydomain.tld, for which mails should be immediately delivered.

But exim refuses to do this: it puts all mail in the queue.
I've noticed that in certain circumstances, the deliverly process is started right away after an incoming message to mydomain.tld, but only when a rush of mails is coming in.
imho, this happened when I played with smtp_accept_queue_per_connection.

Any help would be appreciated.

greets
thomy