rebootscan with windows 98???

hi,
i have intruduced avast to a friend of mine because i think that avast is the best virusscanner at the moment by the way!
But go to the point,i want to know why avast home version can not make a rebootscan in the beginning?
She have a adsl cable connection and she must always make an connection before she can go online?
I have a direct connection and i have windows 2000 home version and avast can make a rebootscan,so why is it not like with windows 98 ?

Thanks,
greetings
Micho

Boot-Time Scan is only available on Windows NT/2000/XP/2003 and its NOT available under Windows 95/98/Me. This is operating system limitation not avast!'s.

thanks!