In late 2002, representatives of Argonne National Laboratory, a government research center in Argonne, Ill., visited Apple headquarters for a confidential product briefing, according to an executive summary prepared by Apple. The document was shown to a reporter by Stephen Bates, a former Apple sales official who says he was fired last year in a dispute over commissions. The representatives were eager to learn more about product plans for "high-performance computing," in which many PCs are linked together to handle complex computing chores. But Argonne representatives didn't learn enough to help them determine whether the products could fit into the lab's computing project, according to the summary.

"They were frustrated that Apple did not give them any indication of future directions," says the summary. "One of the attendees said that he didn't learn anything he didn't already know from the Web and chat sessions."

In written customer comments included in the document, Rémy Evard, now Argonne's chief information officer, said, "With other companies, ranging from small companies to Microsoft and Intel, I learn an awful lot more useful info for my time investment than we got here." In an email, Mr. Evard confirms his comments, adding that he has made such comments to Apple more than once.

Apple can be closemouthed about even seemingly picayune details. Several years ago, David Sobotta, Apple's former director of federal sales, says he accompanied a top technology official of a large National Aeronautics and Space Administration facility to Cupertino. In a meeting one Friday with an Apple product manager, the official wanted to know when Apple would release a version of one of its Mac laptops that could connect to Apple's external flat-screen displays. The product manager declined to say, according to Mr. Sobotta, who joined Apple in 1984 and says he was fired last year over a dispute involving sales commissions.

The following Monday, Apple publicly announced a laptop that included the very feature the NASA official had asked about three days earlier. The official didn't respond to requests for comment. But Mr. Sobotta says the NASA official -- a major customer, who spends millions of dollars a year on Apple products -- was miffed.