I remember learning some years ago in Gemarah Megillah 13: that when Haman drew lots he was happy it landed in Adar since it is the month that Moshe Rabeinu died. However, he didn't know that Moshe Rabeinu was born in that month as well.
How and why would Haman know the birthdate of a Jewish leader? (i.e. why would a gentile care to know Jewish trivia?)
Say Haman knew it from some Jewish sources, Wouldn't it make sense for someone who heard, that on the 7th day of Adar is Moshe Rabeinu's Yahrzeit, would hear in the same sentence, that on THE VERY SAME DAY was Moshe Rabeinu's birthday?