My i320 doesn't print anymore

Hello,

I'm having a strange problem since this afternoon. My Canon i320 doesn't
print anymore. Its last print was done at 15.30 approx. and from this moment
it doesn't print anymore. The system (Win XP) doesn't signal any error in
the printing process, the paper is pulled normally page by page, and I hear
the printheads moving along the paper. But the paper exits the printer as
white as it was when he entered it. Nothing printed. I tried black printing
and color printing without result. The communication process seems normal as
Win XP doesn't tell a thing about a print problem. For the system the
printing was done normally. It's exactly as if there was no ink at all in
the tanks with the printer trying to jet ink that wouldn't be here, but
that's not the case. I have ink in my tanks, I see it when I test the
nuzzles.
I don't understand what's happening.

Any help would be very appreciated.

Thx in advance
Eric