Anti Missionary Law?

I've heard there is an anti missionary law in Israel... I don't understand whether it really exists and how strictly it's being followed. (http://en.wikipedia.org/wiki/Anti-Christian_sentiment#Israel) I've read that you can go even to jail because of that? Is that truth? The reason I'm asking is because my father is going to Israel as a missionary and I'm worried because of him. I personally couldn't care less, but I ask because of him... Please share me some information about it...