Microsoft today filed suit against Funmobile Ltd. of Hong Kong and its Foster City, Calif., subsidiary -- alleging that they used a combination of phishing and instant-messaging spam to steal login information and direct people to adult entertainment sites and bogus social networks.

The suit alleges that Funmobile used instant-messaging spam, known as "spim," to direct people to web sites that deceived them into turning over their Windows Live Messenger login information and passwords. According to the suit, Funmobile then used those logins to break into accounts and send more spim. Tim Cranton, Microsoft associate general counsel, described the case in a blog post today.

"As outlined in the complaint, Microsoft alleges that Funmobile Ltd., a Hong Kong-based company owned by brothers Christian and Henrick Heilesen, has spimmed thousands of Windows Live Messenger customers since March 2009.  The scheme is alleged to target customers with IMs that appear to come from the e-mail address of a known friend or acquaintance, and invite the recipient  to click on a link

"Customers who clicked on the link in the bogus instant messages sent by Funmobile were then “phished”— that is, asked for their IM username and password to log in, according to the complaint. Those who provided the log-in information were often redirected to an adult Web site or, in some cases, a site that claimed to be a social networking community for Windows Live Messenger users.

"Meanwhile, we allege, the defendants collected the wrongfully-obtained usernames and passwords and used them to access Microsoft’s proprietary systems and our customers’ accounts. They then “scraped” or “harvested” the contacts within each user’s account, and sent unsolicited bulk IMs to each of his or her contacts."

TechFlash has contacted Funmobile via email to get the company's comment on the case, and we'll update this post if it responds.