"The jury is still out as to whether this structure is going to work," says retail consultant Bernard. Levi's might think it can fool customers into thinking the jeans on a Wal-Mart rack are "real" Levi's, but he's not so sure customers will understand the $24.99 versus $50 price difference between the pair at Wal-Mart and the pair at Macy's. And if the jeans aren't selling well at Macy's, what makes Levi's so sure it can sell jeans at Wal-Mart?

Others say it's tough for any supplier to turn a Wal-Mart relationship into a gold mine. "Wal-Mart works with their vendors to make sure [Wal-Mart] succeeds," and that's not a guarantee that the vendors make a lot of money, says Paula Rosenblum, a retail analyst at AMR Research. Indeed, a recent Bain survey of more than 20 Wal-Mart suppliers found that very few were doing everything right to gain on both the top and bottom lines (see "What Wal-Mart Wants," right). "The place where companies do fail is when they aren't bringing anything new to Wal-Mart," says Gib Carey, a supply chain analyst at Bain, who studies the company's supplier relationships. "Wal-Mart is constantly looking at 'How can I get the same product I am selling today at a lower price somewhere else?"

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Nonetheless, Levi's was due to start shipping the Signature line to Wal-Mart at the end of May, beginning with 40 stores. By June, Levi's will be ferrying the new clothes to all U.S. Wal-Mart stores in preparation for the back-to-school rush. Bergen expects some bumps during the first three months. But if all goes well, the company plans to sign new deals with other discount retailers too.

"If I look overconfident, I'm not," he says. "I'm very nervous about this change." That's understandable, considering the unchartered waters. "When we trip, we have to stand up real quick and get back on the horse, as they say."

Preferably wearing a pair of Levi's.