Russia claims that it is not providing Iran with missile technology, but also says that private Russian companies may be selling military material that, according to Russian law, are not to be exported. But Iran has successfully tested a longer range (2,000 kilometers) Shahab 4 missile this past Summer. For the last three years, Iran has been working on the shorter range (1200 kilometers) Shahab 3 missile (built with North Korean technology.) The Shahab 3 tests have not been successful, and then, all of a sudden, the Shahab 4 appears and succeeds in its first test. Russian firms apparently provided plans and parts from the obsolete (for the Russians) SS-4 IRBM (Intermediate Range Ballistic Missile.) Since the fall of the Soviet Union in 1991, lots of military technology has been thrown out, and some enterprising Russians have been known to collect some of these Cold War leftovers (like the SS-4, which was the missile sent to Cuba in 1962 and the cause of the Cuban Missile Crises.) The SS-4 was phased out of Russian service during the 1980s. But the knowledge of how to build and maintain the SS-4 remained in Russia, and was apparently sold to Iran, along with key motor and missile body materials (special alloys and parts.) Iran denies obtaining any foreign assistance in its missile development program, but they've always said that, even when spy satellite photos of ships from North Korea being unloaded said otherwise.