As Beijing restricts online dissent and Urumqi clamps down on separatists, Shanghai is cracking down on… (wait for it)… pajama-wearing in public.

The wearing of colorful, boldly-printed pajamas in public has been popular in the city for years, and well-documented on Flickr as well as National Geographic.

But with the 2010 World Expo in Shanghai just three months away, city officials have launched a public etiquette clampdown targeting the unseemly practice.

The South China Morning Post reports that the city's Qiba neigborhood "has mobilized neighborhood committee officials and volunteers since July to talk people out of the habit of wearing pajamas in public."

The article also consults Chinese sociologist Zhang Jiehai, who says pajama-wearing in public began "as a matter of practicality because people lived in cramped conditions with no clear line between public space and private place."

Private pajama parties, anyone?