Facebook contact synch only working when I'm logged onto Facebook?

[Runaway Jim]

I'm new to the iPhone, got my first, the 4, last weekend. I can't figure out if there's a problem with the facebook contact synch or not. I log on to facebook on the phone and synch my friends list. The pictures and facebook addresses go into my contact list like they're supposed to. When I log off of facebook though, they all go away. I figured I just have to leave facebook logged on all the time. A friend of mine disproved that when he showed me, also on a 4, that he synched his friends list in facebook to his contacts and then logged off of facebook and all of the profile pics and addresses still show in his contacts list. What am I missing?