False Rumor Alert
I hadn't even heard this one before, so I guess I should count myself lucky. There's a whole thread of posts on one of the Yahoo! message boards (not Pepsi's board). I won't dignify the rumor by posting it, but here's Pepsi's response:

We wanted to clarify an erroneous report that has been circulating around cyberspace for some time. Pepsi has not created any packaging containing an edited version of America's Pledge of Allegiance. A patriotic package used in 2001 by Dr Pepper (which is not a part of PepsiCo) was inappropriately linked to this rumor. Dr Pepper's position is very clearly articulated at: http://www.dpsu.com/drpepper_can.html.

And Dr. Pepper says:

A Note to Dr Pepper Consumers:

In February 2002, several news media outlets in the country reported on a special edition Dr Pepper can that was created to show support for the patriotic fervor that has been sweeping America since the tragic events of Sept. 11, 2001, and to show the world that we are a united nation of people who place a high value upon freedom.

Much of the information being circulated on this subject, especially on the Internet, is incomplete or inaccurate. Here are the facts:

The can, released in November 2001, features an image of the Statue of Liberty along with the words "One Nation … Indivisible." The special packaging was designed to reflect our pride in this country's determination to stand together as one. The Statue of Liberty and Pledge of Allegiance were chosen as two of the greatest symbols of American freedom. Only three words were used from the Pledge of Allegiance. Those three words were in concert with the patriotic mood of the nation.

We at Dr Pepper/Seven Up strongly believe that the message on these cans is a resoundingly patriotic message that we are a united nation.

More than 41 million special edition cans were ordered by Dr Pepper bottlers in portions of a dozen states. The limited edition patriotic was retired in February 2002 and will not be used again.