Printing without margins

Hi

I’m using

 Canvas.printComponents(Object[] components)

to print a html with firefox. I’d like to print without margins on the sides or with small margins, but I can’t manage this. The Page Setup of firefox is not taking effekt on the margins: something like 9, 10% of the width on the left and on the right side are always blank spaces. How can I set the margins size?

Thanks in advance

Ts. Vasilev