Question about URLRequest

[Jazztronik]

I'm a little lost with regard to two properties of this class:

contentType
requestHeaders

Is there any direct correlation between them?

As far as I know contentType is used to specify the MIME type of the data to be sent, whereas requestHeaders is an array which contains each header. So, what if I write something like this?:

var headers:Array = new Array(new URLRequestHeader("Content-Type", "text/html"));
myURLRequest.requestHeaders = headers;
myURLRequest.contentType = "application/octet-stream"; // instead of "text/html" 

wouldn't it be an incongruity?? I'm not very keen on HTTP headers so I'm not sure if both refer to the same thing or not.