A clarification of the thread above from the horse's mouth:

Microsoft is set to enter the security arena next year, but Symantec won't compete by complaining to antitrust regulators or suing the software giant.

"We're not looking to go whining to the EU or the DoJ for anything," Symantec chief executive John Thompson said...

Symantec has responded to questions from EU competition authorities about its role in the security industry, but has no intent to file a complaint about Microsoft, Thompson said....

"We're not involved with anything with the EU," Thompson said. "We don't need competition in the courtrooms."

A news report last week said Symantec was complaining to the EU about Microsoft, specifically concerning possible bundling of security software with Windows.

The full text of this story can be found here.