It not a walk in a park but within reach.The solid-propellant technology demonstrated by the Sejil gives the Iranian a key for longer-range missiles that could be deployed in a survivable manner from Western Iran. They took the Shahab, extended it a bit, added a new lightweight second stage, and now they have the Safir space launch vehicle.
The IAEA inspectors just in Iran were there to inspect the solid-fuel rocket facility at Parchin. They were quickly refused access.
Iran is going full speed to develop solid-fuel as that is the key to range-payload of their rockets.
The inspectors could have also noticed any, say, N Korean smiling faces at Parchin also.