At work, we use Google Apps to host our e-mail and Outlook to access it. I have a user who recently changed their name. I changed their e-mail address and their account name, but when they send e-mail their old name still appears, no matter whether they send it using Outlook or the gmail web client. For example, e-mail from them in the Gmail web client reads Oldname [email protected] instead of Newname [email protected]. I'm trying to make the user's new name show up when they send an e-mail.

Where is the sender's name stored? Is it a part of the e-mail specification, stored in some header somewhere, or is it stored in the e-mail client?

If it's possible, how do you change the sender's name in Gmail?