Give credit where credit is due...
http://www.interactivebrokers.com/en/software/releaseNotes/TWS_Notes_871.php?ib_entity=#871_fix
"If TWS temporarily lost the connection to the market data server, in some cases the connection was not restored properly and the quotes on the screen would appear frozen. This is fixed."
http://www.interactivebrokers.com/en/software/releaseNotes/TWS_Notes_871.php?ib_entity=#871_fix
"If TWS temporarily lost the connection to the market data server, in some cases the connection was not restored properly and the quotes on the screen would appear frozen. This is fixed."