It is only illegal if someone says it is. And in this case since it is an Islamic leader then no one will say it is illegal.
"If Jews and Christians, so often on the receiving end of the most hateful forms of expression, can overcome our revulsion in the service of liberty, so too can our brethren in the Islamic world. To expect anything less of Muslims is to debase them and their faith – far more than any cartoon ever could."
Is there a "cleric school" where these small minded people go to learn how to teach hate?