“Request-URI” HTTP field in .NET HttpWebRequest class

I would like to create HTTP-request with method OPTIONS using an object of HttpWebRequest .NET-class. RFC 2616 says that this request should look like this:

OPTIONS * HTTP/1.1

where "*" (asterisk) is value of the "Request-URI" field and means that the request apply to server itself, not to some resource.

Request with method OPTIONS works, but in fact it looks like this:

OPTIONS / HTTP/1.1

Is there a way to specify "*" (asterisk) value to "Request-URI" field of the HTTP-request using HttpWebRequest .NET-class?