How to Change a Message's Priority in IncrediMail

"To bring worker into the country may prove significant," said the paper on, I believe, a Sunday morning. It expected you to do something with this information, too: fill in nine blank spaces with letters that satisfied Mel Taub's clue as a crossword puzzle solution — and as a pun.
Well, here's another hint:
›› Choose a special IncrediMail letter, and high priority, too, for your important messages.