A United gate agent checks passengers in by hand at the United Airlines terminal at Chicago's O'Hare International Airport Thursday, July 2, 2009, after a computer problem temporarily disrupted United Airlines flights at O'Hare International Airport on Thursday, causing long delays and lines for travelers headed out for the Fourth of July holiday weekend. AP Photo logo AP Photo 32 months ago

A United gate agent checks passengers in by hand at the United Airlines terminal at Chicago's O'Hare International Airport Thursday, July 2, 2009, after a computer problem temporarily disrupted United Airlines flights at O'Hare International Airport on Thursday, causing long delays and lines for travelers headed out for the Fourth of July holiday weekend.