According to security researcher Brian Krebs, the wave of scareware being peddled to Skype users is something of a first in the complex world of internet scams.
One quick-thinking reader, he says, managed to record the tail end of the automated call, which he has posted online.
The call says that "to download the patch update, request professional maintenance at www.sosgt.com."
Krebs says that it seems from reports on the Skype.com user forum that a great many others are receiving these rogue IT security calls.
"If you visit that site (probably best to avoid it), your browser is immediately shown what I call the `scamscan' pop-up screen made to fool you into thinking there are a ton of threats on your machine that need neutralising", says Krebs in his latest security blog.
According to the security researcher, the curious feature of these fake scans is that they will tell you that your machine has Windows-based malware, whether you browse the page with a Windows PC or a Mac.
If users then click on the `Erase all Threats' button in the pop-up generated by the site, Krebs notes that users are taken to a page that offers you `professional online repair service,' and they offer both Mac and Windows plans.
"Another odd twist is that this scam, which ultimately redirects the user to secureonlinestore.net, leverages the online payment platform of SWReg, one of several automated software payment processing systems run by legitimate processing firm Digital River", he said.