PALO ALTO, Calif.--Adobe Systems’ Acrobat software and the PDF documents it creates are often referred to as electronic paper, but for consumers they’ve been more like a stone tablet--impervious to any user alteration.

That’s starting to shift, according to current and former Adobe executives, as the format changes to handle new data demands. Additions using the XML Web services language and other tools will allow people to add signatures to PDF (Portable Document Format) documents or make formatting changes, for example.

"At one point, Acrobat was known as the roach motel of data formats--you could get data in, but you couldn’t get it out," Adobe CEO Bruce Chizen said here Wednesday night during a panel discussion run by Silicon Valley’s Churchill Club. "That’s not true anymore. Acrobat is this big container for doing things."

John Warnock, chairman and co-founder of Adobe, said on the panel discussion about Adobe’s past and future that the airtight Acrobat approach still has value. "Signed documents are really good for that," he said. "You want the information to be embalmed."

An expanding role for Acrobat has become the centerpiece for Adobe’s vision of "network publishing," in which information in documents can be freely shared across a variety of formats--from Web pages to printed material. The drive gained new attention last week, after Microsoft unveiled xDocs, an initiative intended to merge data from online forms with back-end business software. The project has drawn comparisons to Adobe's plans with Accelio, a Canadian software maker it acquired for its online forms software.

While he refrained from belittling the Microsoft effort, Chizen noted that Adobe has staved off threats from the software giant in the past, such as the TrueType font language intended to kill Adobe's PostScript franchise.

"Microsoft is a $30 billion company--I'm always going to lose sleep over Microsoft," Chizen said. "But the lesson I learned…is that as long as we stay close to what we do well, things that help people communicate better…we'll do better than Microsoft."

Adobe co-founder Chuck Geschke also defended the company's record of pushing technological limits, such as introducing a sophisticated image-editing application--the profitable Photoshop franchise--at a time when hard drives barely had room to store one high-resolution image.

"I'm not a hunter, but I've been told that if you want to hit duck, you don't shoot where the duck is. You shoot where it's going to be," he said. "We always designed products…based on where we thought the technology was going to be."