Looks like Facebook's billionaire founder and Harvard's famous dropout Mark Zuckerberg still has the option to return to his alma mater to finish his degree.

Harvard University President Drew Faust, speaking to an audience at Facebook's California headquarters, remarked that Zuckerberg is considered to be on leave from the University, which he had left in 2004 to work on his social networking site.

"When I talked to Mark in January he said he still has his Harvard email, so he is still on leave," Faust joked with the company's staff and interns, many of whom were Harvard alumni and current students.

A report in the Harvard Gazette website quoted Faust as saying that Harvard encourages gap years and international travel, which have become popular options for undergraduates. And the door remains open for those who would like to return to finish their degrees- including Zuckerberg, Faust added.

Faust said Harvard should adapt to the new culture of openness and flexibility brought about by the Internet. "Taking a year off from Harvard - to start a company or follow an opportunity abroad, for example - no longer carries the stigma it once did," the report added.

"I really believe universities should not have fixed ideas about what students should do or where they should go," Faust said.

"Instead we should give them the intellectual and other resources of advice and support and information that enable them to make the choices that are best for them and best for the world in which they are going to live."

Faust said Facebook and the University share a similar focus in the age of information overload.

"In a sense, Harvard and Facebook both serve as filters of information," Faust said. "You filter information through social graphs. We try to teach people to be interpreters and critical evaluators of information, to identify how to use information."

Harvard students use Facebook to form study groups and learn from one another outside the classroom and social networks play a large role in breaking down barriers, she said. "Universities do not have walls anymore. Knowledge is global and the way it is reaching out is global."