It was an op-ed in the NYT : http://www.nytimes.com/2006/01/24/opinion/24leverett.html Firstly, what he actually says is that Iran "acknowledges" it would have to address concerns about Israel. This is not the same as being willing to accept the beirut proposal or accepting Israel or stopping support of terror - terrorists who incidently killed hundreds of americans, it is in fact not even close, it simply a statement of of indisputable fact that these were ongoing issues between the two countries. Secondly, Leverett didn't see this document - he "heard" about it from Goverment friends. So what we have is third-hand hearsay, about a country running scared in the brief moment of haitus in Iraq...
Justice Ministry: Information examined by AG about Gal Hirsch didn't come from police (Haaretz)
from the article: Is America a strategic liability?