Why does Greenwald believe that the charges against the two are dubious? This article putatively condemns US policy vis-a-vis Iran, but it bolsters the prevailing anti-Iranian propaganda by insisting the detention of the two "hikers" was unwarranted.
I don't know if these two are spies, but Iran is crawling with Western spooks, they very well could be. Greenwald and Democracynow are doing the devil's work by lionizing the two who at best were incredibly reckless.
http://www.informationclearinghouse.info/article29220.htm