Thanks for your quick answer.
But a Mail, which is delievered after greylisting should be delivered next without greylisting, right?
We have special situation.
A mail, which is Greylisted, was delivered after 7 tries (03:33pm, 15:39pm, 3:39pm, 4:33pm, 5:19pm, 5:23pm; 5:30pm=greylisted...