Validator not consider the pattern attribute

Hi,

The attributte "pattern" is not considerated for W3C Validator Markup.

Look at this exemple
http://validator.w3.org/check?uri=http%3A%2F%2Frapordo.com&charset=%28detect+automatically%29&doctype=Inline&group=0
(http://validator.w3.org/check?uri=http%3A%2F%2Frapordo.com&charset=%28detect+automatically%29&doctype=Inline&group=0)
In this case, the Validator show 3 errors because i use one regular
expression in attribute "pattern", but in this case "&" is not incorrect..

Thaks!

 (http://rapordo.com/otavio)
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