Yes, it is from 2010 and is much more serious **** than, "John Brennan called me.".
This is the indictment: https://www.justice.gov/opa/press-release/file/1153486/download
After uploading the “Apache video” of the US killing 2 Reuters journalists, and a group of Iraqi Civilians to a WikiLeaks dropsite, Manning was contacted by someone at Wikileaks who went by the name of “Nathaniel” and that was who Manning suspected was Assange. They began an almost daily correspondence over the Jabber networking site.
The person who Manning spoke to never identified himself as Assange.
During Manning’s Trial a US military representative testified that nothing Manning released endangered operational security.