Element h10, validating HTML5

Hello,

I've some issues with validating my website. (HTML5)
After doing the validation, i receive some output errors:

2 of the most important validation Output errors:

    Error Line 61, Column 49: Element script must not have attribute
charset unless attribute src is also specified.

            <script type="text/javascript" charset="utf-8">


    Error Line 277, Column 121: Element h10 not allowed as child of element
a in this context.
       (Suppressing further errors from this subtree.)

    …lass="textwidget"><a href="/over-ons"><h10>Over Ons</h10></a><br />

The supportlink transparant didn't bring me further.
http://dev.w3.org/html5/spec-author-view/content-models.html#transparent

Do you know how to allow element h10 as child in this context? Or isn't it
possible?
How to solve this issue, i got 15 more of exact these issues in my website.

Thanks for your support in advance!

Best regards,

Gerard Vlokkentest
http://www.eigenwebsite.nl