Despite Microsoft placing a June 30 deadline on Windows XP, with all sales of the OS being cut off following that date, three of the world’s largest PC manufacturers are exploiting loopholes in Microsoft licensing terms as a means of supplying XP beyond its official kill date.

Specifically, Dell and HP are exploiting a clause in the downgrade rights that come with Vista Ultimate and Business that enables those buying these versions of Vista to have the option of downgrading to the older version of the operating system and keep it under the same Vista license. Lenovo, for its part, is including an XP recovery disk on some Vista-based systems, allowing owners to revert to the older OS if they choose to. Microsoft certainly isn’t going to be too happy about this, especially now that Vista Service Pack 1 is out.