Researchers at the Avert Research Center say they've discovered the first virus that spreads on the Palm OS. The virus, known as PalmOS/Phage.1325, is considered a low-risk threat that can be spread via E-mail, Web-site download, infrared file transfer and PC-to-Palm synching.

Phage, which is Latin for "one who eats," was reported by Network Associates' Avert center late Thursday evening. A Yahoo! E-mail user contacted the center to report a possible virus. According to Avert, when an infected application is run, the screen goes black and the program terminates. Phage then sets about infecting other apps on the device.

"We've been predicting a PDA virus for some time now, and it's finally happened," says Vincent Gullotto, director of McAfee Avert.

Phage makes it appear as if files have been deleted, when it fact they haven't.

In testing, when a new program is copied to the Palm system through infrared transfer, the program will appear to run normally. However, once it is closed and run again, it becomes infected and will not function.

Avert is advising users to delete infected files; recovery requires a hard-reset followed by a hot-sync of the PDA. A cure for Phage has been posted at avertlabs.com.

"This won't spread like wildfire," Gullotto said. "This is currently a low-risk virus. We've only had one report, so we don't know how many infections there are. It could have been the virus writer who sent it to us, for all we know."

But he warned of copycats. "I'm sure more will come."