Microsoft has apparently been telling executives at a top PC firm not to expect the first service pack for Windows Vista - SP1 - until 2009 at the earliest.

This throws the launch of the next version of Windows (codenamed 7, formerly Vienna) into doubt, possibly pushing it back as far as 2010 - something that Microsoft has hinted at anyway.

All of this, Valleywag explains , is why Microsoft has been so keen to play down an early launch for SP1, which was originally supposed to have surfaced last week .

PC makers disappointed

If true, the news will compound the misery some PC makers are feeling. Many had expected a hardware sales boom after Windows Vista launched in January. That didn't happen. Acer President Gianfranco Lanci told Financial Times Deutschland :

"The entire industry is disappointed by Windows Vista... And that's not going to change in the second half of this year."

Microsoft plans to launch a beta version of Windows Vista SP1 later this year.