ISIS has “a copy of Iran’s response”:http://www.isis-online.org/publications/iran/iranresponse.pdf to the “P5+1 package”:http://www.armscontrol.org/pdf/20060606_Iran_P5+1_Proposal.pdf offered to Iran 6 June.
There’s also a “brief analysis”:http://www.isis-online.org/publications/iran/confusedbuthopeful.pdf which you should read.