The marketing site that the Mozilla Foundation sponsors to spread the word about its open-source browser was hacked July 10, and taken offline for several days last week as the group investigated the damage.

"We don''t have any evidence that the attackers obtained personal information about site users, and we believe they accessed the machine to use it to send spam," read the e-mail Mozilla sent Friday to registered users of its Spread Firefox site. "However, it is possible that the attackers acquired information site users provided to the site."

The breach was discovered July 12, and the site was taken down as a precautionary measure for several days before going live again on Friday, July 15.

"To be safe, were encouraging all of our users to log in and change their passwords," wrote Asa Dotzler, an engineer with Mozilla, in a blog entry on the Spread Firefox site Friday.

Spread Firefox collects and stores a name, URL, e-mail address, IM names, and street address on its servers. Only the password is encrypted, according to Mozilla.

"The Mozilla Foundation deeply regrets this incident and is taking steps to prevent it from happening again," Friday''s e-mail continued. "We have applied the necessary security fixes to the software running the site, have reviewed our security plan to determine why we didn''t previously apply those fixes in this case, and have modified that plan to ensure we do so in the future."

Some Firefox users immediately spun out conspiracy theories that accused Microsoft of hiring hackers to take down its competitors site. "This is crystal clearly the deviousact of [Microsofts] hired goons," a user identifying himself/herself as "c4p0ne" wrote on BetaNews.

Others took the unfounded claims to task. "This isn''t some sort of master plan by microsoft, its [sic] some kid who decided it would be fun to hack a page," wrote Metshrine on the same site.

The gaffe was the second suffered by Mozilla last week. It also has had to rush another version of Firefox, 1.0.6, into development because the security update of 1.0.5 prevented some browser plug-ins, or extensions, from working.

Mozilla''s other Web sites, including its primary Mozilla.org site, were not affected.