Professional networks on Facebook are intended to be limited to employees, and require a corporate e-mail address to which Facebook sends a confirmation e-mail to verify accuracy. But when MySpace launched MySpace Mail this summer, it made e-mail addresses with the myspace.com domain--which is also used internally for corporate e-mail--available to any members of the News Corp.-owned social network.

A reader tipped off CNET News to the hack, which requires a little bit of HTML know-how. We're not going to give detailed instructions out of the interest of MySpace employees' own security--and it looks like Facebook has put a fix in place, because when a CNET colleague used a MySpace Mail address to register around 2:40 p.m. PT on Wednesday, he was informed that the address was invalid.

In vague terms, it looks like MySpace was aware of the fact that members might try to register for its network on Facebook, because the confirmation link to Facebook does not work in MySpace Mail, nor does copy-pasting it. Basically, it's mangled somehow. But, the tipster explained, the real link is still in the page's HTML source. And indeed, I was able to join MySpace's network on Facebook.

More: http://news.cnet.com/8301-13577_3-10370015-36.html

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