New KMail feature

When opening a message in KMail, there is a gray rectangle area above the message containing the basic To/From/Subject information. In Trinity there is a blue box at the right side of the gray area. The blue box uses a gradient background and contains the current time of the person who sent the message. There is a related configuration option in Appearance, Message Window, named "Show current sender time." How is the current sender's time being determined? Is this a local calculation or is KMail fetching data from somewhere online before calculating and displaying the time? Thanks. Darrell