Not so fast. It's almost certainly a ploy to calm things down. Here's what he actually said:
"Thanks God Almighty, the elections were held well with high degree of reliability, soundness and tranquility. You too should follow up relevant issues through legal channels."
Another official take:
Presenting a report during this meeting, which took place yesterday afternoon, Mr Musavi expressed his point of view on the process of elections. Stressing the importance of maintaining calm and dignity, the eminent leader pointed out that in previous elections, too, some individuals and candidates had certain concerns which were followed up through the Guardian Council, which is the legal authority for looking into elections complaints. The leader added that naturally in this round of elections too, issues should be followed up through legal channels. Pointing to Mr Musavi's letter to the Guardian Council the leader said: The Guardian Council has been notified to give the letter its careful consideration.