The Ron Paul contingent just made itself heard during the presentation of credentials, with noticeable booing and heckling. Chairman Priebus appeared less than happy.
Watch the events over at CSPAN.
Update, 4:25 pm -- Paul delegates now shouting "Point of Order" while Sununu presents rule changes to convention. Audible frustration.
Update, 4:40 pm -- Paul's Maine delegates have now walked off the convention floor, per Buzzfeed's Rosie Gray.