Can double content be a reason to not have PR?

[kenbrother]

In a bigger project are several domains that show the same content like the main-site (there is a reason to have it like that). Now those "double-content domains" are indexed and ranking in Google. But now I see that all those double-content domains have no pagerank visible, despite they do all have their unique own backlinks.

Do you know why those domains don't show Pagerank? Can it really have something to do with the double-content situation?

[HiveDigitalInc]

PageRank is content unaware - it is solely a measurement of link popularity. The PageRank remains zero for these pages because, more likely than not, Google has simply not updated the Toolbar PR. What is the MozRank for these pages?