ICS corrupting images over network

I have one desktop with dial-up connection and ICS configurated.
This PC shares the connections with another 2 laptops by a D-Link wireless
router.

I did test there 2 laptops and this router in another 2 networks and they
worked fine, but in my home with dial-up connection the some images and pages
are corrupt on the laptops, but in the host PC it works fine.

Sample:
Corrupt: http://brtones.com/temp/corrupt.jpg
Right: http://brtones.com/temp/right.jpg

Is that a Vista ICS problem?