As discussed on thread, not banned, but posting it somewhere could get you in significant trouble. In fact, Phil Zimmermann got in quite a bit of trouble for his contribution towards the world getting a hold of PGP, which was considered a export restricted munition. I believe there was at least one court case, harassment, tax audit, and hassle at the border. My memory is a big vague, but you get the idea.
I was at codecon, forget if Zimmerman was there, or just quoted. His story was recounted, then someone else who attended codecon and mentioned releasing ITAR restricted crypto. They were part of a leak of the RC4 source code. A copy was sent to a well known member of sci.crypt, saying along the lines of "I think you can post this anonymously", if you agree to this please post a "Looking for Joe Random" post on sci.crypt. The source code was posted and there was no lawsuit, no tax audit, and no hassling by the government.
I was at codecon, forget if Zimmerman was there, or just quoted. His story was recounted, then someone else who attended codecon and mentioned releasing ITAR restricted crypto. They were part of a leak of the RC4 source code. A copy was sent to a well known member of sci.crypt, saying along the lines of "I think you can post this anonymously", if you agree to this please post a "Looking for Joe Random" post on sci.crypt. The source code was posted and there was no lawsuit, no tax audit, and no hassling by the government.