What ban ?

Interestingly, this turns out to be quite controversial.
http://www.bbc.com/news/world-europe-30813742
http://www.bbc.com/news/magazine-30814555

"There is no specific, or explicit ban in the Koran on images of Allah or the Prophet Muhammad - be they carved, painted or drawn."

"Shia Islamic tradition is far less strict on this ban. Reproductions of images of the Prophet, mainly produced in the 7th Century in Persian, can be found."

"Siddiqui points to depictions of Muhammad - drawn by Muslim artists - dating from the Mongol and Ottoman empires. In some of them, Muhammad's facial features are hidden - but it's clear it is him. She says the images were inspired by devotion: "The majority of people drew these pictures out of love and veneration, not intending idolatry."

"The prohibition against depiction didn't stretch everywhere though - many Shia Muslims appear to have a slightly different view. Contemporary pictures of Muhammad are still available in some parts of the Muslim world, according to Hassan Yousefi Eshkavari, a former Iranian cleric, now based in Germany."

But...

"Dr Azzam Tamimi, former head of the Institute of Islamic Political Thought told the BBC... He is not convinced by the argument that if there are medieval depictions of Muhammad that suggests there is no absolute prohibition. "Even if it were that would have been condemned by the scholars of Islam.""
http://www.bbc.com/news/magazine-30814555