FireFox shows gray borders where IE shows none

[Beanster]

I've been paying more attention to my website design based on the number of FireFox visitors we have.

On our pages, we have a table specified with no border (0 - zero border) and one table specified with a white border with the cell border also white.

This looks perfect in IE but Firefox shows a gray border on both tables.

I use Dreamweaver MX 2004 for site design.

Any ideas why this happens?

[choster]

Welcome to WebmasterWorld.

It often helps if you post a relevant snippet of your source code.

[CritterNYC]

Design first for Firefox/Opera/Safari and other standards-compliant browsers... and *then* add in the hacks to make them work right in IE 5.5, 6 and 7's buggy renderers.

[FromBelgium]

You probably use "BORDERCOLOR" which is not an official attribute for <table>. Firefox does not accept this attribute but IE does.