How can you add to the list of allowable charcters or character sequences?  For instance, what if we want to allow "<br>" tags?  If this is not possible with the current version of the library, please consider an extensible approach for the next version.

Thanks! 

It appears that the Anti-Cross Scripting Library v1.5 doesn't have a feature where you can define an allowable set of HTML tags.  I sent an email to Scott Guthrie and he forwarded my question to Stefan Schackow, who suggested I post a feature request to the team that is responsible for maintaining the XSS library.

It you would like this type of feature in the XSS library, please leave feedback for the team via this blog:

 http://blogs.msdn.com/ace_team/default.aspx