VWD/Asp.Net 2/C# - Menu error parsing control urI cannot be created

I have the web.sitemap file set up with nodes that work according to the sitemappath control. I also added the menu after adding the sitemapdatasource.
But I still get the error error parsing control uri cannot be created because the uristring parameter represents an absolute uri.

http://foo.no-ip.org/images/sitenav.jpg

Please explain what this means, what is a uri? What am I doing wrong?Ok, I see that the problem lies with this line:

<siteMapNode url="mailto:admin@.comcast.net" title="Contact" description="Contact Author" />

Trying to add a mailto link in the url for contact just causes problems. All the other links work file for each node. How can I correct this?
That control, in design view, is attempting to re-render your URLs such that they are relative to the page on which you are currently on. Now, a URI is a superset of URL. URIs indicate the location of something in terms of actual existence or simply patterns. So for your purposes, consider them the same. When you get into advanced XQUery/XML, the differences become clear.

Ok, so as I was saying, it's attempting to create a relative URL, but you've used a mailto: URL instead of http://, and it doesn't know what to do with it, so it gives you that warning.

Therefore, don't do this in the design view, but do it from a configuration file or from the design view. Let it display that warning, it shouldn't cause a problem though.
That'll work, or I guess I could just create a contact page and add that to the sitemap file.

Thanks for the knowledge.
Contact pages are always nicer. I don't like browsers opening my default mail client.