Hyperlinks Instead Of LinkButton - How To Avoid Border Around Image

I have an ASP.NET web site which contains some ImageButton controls that cause postbacks used to filter a list of products to certain groups of products.

The ImageButton was created something like this:

ImageButton _myImageButton = new ImageButton();
_myImageButton.ImageUrl = PicturePath + PictureName;
_myImageButton.Attributes.Add("border", "0");
_myImageButton.OnClick += handleImageButtonClick();
Controls.Add(_myImageButton);

Now I am moving to ASP.NET 4.0 with SEO-friendly paths like /products/category/item, and I'm using routing with Webforms to map URL's to webforms. In the process, I want to replace my image buttons with hyperlink controls showing the image, so that I can associate a navigational URL with each image.

I'm creating my new image hyperlink something like this:

HyperLink _myImageLink = new HyperLink();
_myImageLink.ImageUrl = PicturePath + PictureName;
_myImageLink.NavigateUrl = "/products/category/" + itemName;
_myImageLink.Attributes.Add("border", "0");
Controls.Add(_myImageLink);

The big problem I'm facing: the ImageButton used to put a border="0" attribute on the <img> tag in HTML to avoid a border around the image. But how can I achieve the same result using the hyper link control?

With the current setup, the border="0" gets stuck onto the <a href="...."> tag - and that's not exactly what I want / need.