This is strange, because Zeresh already knew that Mordechai was Jewish - Haman himself told her! (5:13)
So what was Zeresh talking about?
Another question: How did Charbonah know that Haman had built a gallows for Mordechai, when he suggested to the King that Haman be hung on it? (7:9) Only Haman, his family and friends knew about the gallows!
And furthermore: How did Esther, out of all the virgins in the kingdom, manage to find favor with the King? The odds were pretty astronomically against that happening!
The answer to all of these questions is, clearly, the Israeli Mossad had infiltrated Persia, and these Zionists were cleverly positioned to convince (or force, if necessary) the King to allow Jews to return to Israel.
Esther was a Mossad agent, of course, but she had help. The king's chamberlain Hegai was one of the most brilliant Mossad scientists ever, and he was in charge of perfuming the women who had to attend to the King. Using secret Zionist pheromone techniques, Hegai ensured that all of the women - while they looked good - smelled terrible.
Esther, who refused to wear perfume (at the suggestion of Hegai - 2:15) therefore had a great advantage after months of the king having to put up with smelly Persian women. Clearly the Mossad was behind this operation.
But it didn't end there. Zeresh was a paid informant for the Mossad, as we could see from her "noticing" that Mordechai was a Jew, something she knew quite well. What she also knew was that Haman* was going to his doom, and she would never see him again - so she couldn't resist one last dig at her husband, whom she only married at the behest of the Mossad to begin with.
And Charbonah was her "handler." The gallows that Haman built was Charbonah's idea, and he suggested it to Zeresh - who in turn told Haman. Charbonah, a highly-placed Mossad agent in service of the King, cunningly planned Haman's ironic means of death down to the last detail.
All of this was part of a huge Zionist plot meant to have Esther become queen, give birth to Darius who would then allow the Zionists to move to Palestine and usurp the natives who had lived there for decades.
It is all so clear!
(Last year's Purim Torah, on rock and roll, here.)
(*2010 update: I clearly was at the point of "ad d'lo yadah" when I wrote this last year, as I originally wrote "Mordechai" instead of "Haman.")