http://onionworks.net/2004/renderengine/web
getHeader (parameterName : string) : string
The request headers sent by the client can be read out by means of this method.
<xsl:value-of select="web:getHeader('User-Agent')" />
The request header and additional Informations can be viewed in the request Monitor .This monitor is accessed by the handler "trace.axd". For example: http://my-domain/project/preview/trace.axd.