Human error is to blame for an offensive link at Wal-Mart's (WMT) Web site that recommended a film about Martin Luther King Jr. to potential buyers of a "Planet of the Apes" DVD, the retail company said Friday.

The mistake resulted from a well-intentioned effort to promote a DVD about the black leader, said Carter Cast, president of walmart.com, the online shopping arm of Wal-Mart Stores Inc.

A business manager had grouped "Martin Luther King: I Have a Dream" with three other black-themed movies and assigned the package an overly broad category of DVD boxed sets, Cast said.

So when an online visitor looked at a listing for the boxed DVD set "Planet of the Apes: The Complete TV Series," the black-themed movies appeared under "similar items."

Cast said the display juxtaposition may have existed for the past year.

Wal-Mart removed the feature from its Web site Thursday after learning of the juxtaposition from reporters. Wal-Mart apologized and shut down indefinitely its entire online system for referring shoppers to other movies.

Cast said there was no racist motivation.

"There was nobody here who maliciously put together that combination," Cast said by phone from walmart.com's headquarters in Brisbane, Calif. "I know the person was well-intended in trying to get the 'I Have a Dream' speech out as a cross-sell."

Walmart.com uses a different system than do many other big online vendors to create cross-selling links. Amazon.com, for example, bases recommendations on what a shopper has bought before and what other consumers who buy a certain item also purchased.

Walmart.com manually assigns movies to specific "item display groups," such as science fiction or African-American culture. The company's internally developed software then generates links guiding shoppers to other movies in that group.

Beside the "Apes" boxed set, the King package could have been linked to any of a random selection of other boxed set titles from a group of more than 260, including "Best Of Hitchcock, Vol. 1 (Collector's Series)."

Cast said walmart.com would only start cross-referencing movies again once it has a new system in place to avoid a repeat. That could be a technology more like what Amazon.com uses or another approach, he said.

"We are looking at a bunch of different solutions right now," Cast said.