Sitecore - Illegal characters in path

Meh.


        /// checks for the existence of illegal characters in the URL, these being " < > | and SPACE
        /// for some reason Sitecore's Sitecore.Pipelines.PreprocessRequest.FilterUrlExtensions pipeline
        /// component doesn't handle the exception
        ///
        /// FilterUrlExtensions.Process > Sitecore.Web.RequestFilter.Process > RequestFilter.IsBlocked > RequestFilter.GetExtension
        ///     > System.IO.Path.GetExtension > System.IO.Path.CheckInvalidPathChars = where it goes bang, and isn't handled
        ///  
        /// This component fixes this behaviour by stripping illegal chars and then re-writing the URL using HttpContext.RewritePath
        ///
        /// Note that for some reason, if IIS Static File Compression is enabled for the site, this can cause resources to
        /// be returned to the browser with the correct encoding type (GZIP) but the browser fails to parse them
        ///
        /// Don't know why this is
        ///
        /// For this reason, the URL is only rewritten if the request URL contains these illegal chars

Let's just say this has caused problems with custom pipeline components I have worked on.