About Unicorn

Dear sirs,
I've been a Unicorn supporter for a long time.
I knew you made some changes from the last time I used it (before summer 
2008) hence I tested my web-page ( http://simosito.it/test ) with 
Unicorn itself.
The page is valid XHTML 1.1 and CSS 2.1, as the other validators say.
Nevertheless when I run it through Unicorn it says:

    /Line 4615 Column 0 /: character "]" not allowed in declaration subset

my guess is that it is trying to validate the DTD too, failing.
I just wanted to let you know this.

Your faithfully,
Simone Ramacci