EU antitrust regulators have granted Microsoft a one-week extension to respond to charges that the software giant abused its dominant market position by bundling Internet Explorer with Windows. This is the second extension Microsoft has received and gives them time until April 28 to come up with an answer – the original deadline was January 15.

But while the tiny extension gives them some additional breathing room to plot their next move, the courts have also recently granted “interested third-party” standing to the European Committee for Interoperable Systems (ECIS), whose members include Adobe, Corel, IBM, Oracle, RealNetworks, and Sun. Browser makers Mozilla, Opera and Google had previously joined the case, as well, voicing their concern about Microsoft’s practices.

The participation of all these technology heavyweights highlights the rising importance of controlling internet browser technology as more and more services are being accessed through the web. If found guilty of abusing its dominant position, Microsoft could be forced to pay a hefty fine and/or bundle rival browsers with Windows, even while others such as Apple and every Linux distributor are not required to do the same.