In my previous post on the DNNMenu and SEO, I discussed testing user-agent strings and creating custom browser detection files. As part of my testing I created a simple web-app that allows you to validate your browser capabilities. By navigating to the test site, you can see exactly which features are enabled for your specific browser. To alter how ASP.Net reports the capabilities for a specific user agent, create a custom .browser file and add it to the App_Browsers folder in your website. See MSDN for a complete discussion of the browser definition file format.
The below sample shows the capabilities I have configured for the Yahoo! Slurp web crawler. This is not a definitive list of capabilities, but rather some custom values that I needed for my testing. Feel free to alter this file as needed to more fully emulate the features supported by the Slurp engine.
<browsers>
<browser id="Slurp" parentID="Mozilla">
<identification>
<userAgent match="Slurp" />
</identification>
<capabilities>
<capability name="browser" value="Yahoo!Slurp" />
<capability name="crawler" value="true" />
<capability name="cookies" value="false" />
<capability name="css1" value="true" />
<capability name="css2" value="true" />
<capability name="javascript" value="false" />
<capability name="tables" value="true" />
<capability name="w3cdomversion" value="1.0" />
<capability name="xml" value="true" />
<capability name="tagwriter" value="System.Web.UI.HtmlTextWriter" />
</capabilities>
</browser>
</browsers>
The screen below shows a short list of capabilities detected for Firefox 3.

Download the BrowserCaps web application