Adding an inline image into an AS3 created email

I get the error:
SecurityError: Error #3769: Security sandbox violation: Only simple headers can be used with navigateToUrl() or sendToUrl().

with the code below. I just want the users email system to open and create a new email but have a jpg image inserted inline (not attached). Something like:

Hello welcome to....

   image here

Thanks for visiting...

Maybe since "image/jpeg" doesn't work as a content, is there a workaround? The only other option is to copy the image to the clipboard and have the user paste it into the email. Other than that, I'm at a loss as what to do.

I cannot go the typical route of sending the image to a server and having it send out the email. I already have that working but do to the new security laws in the UK, I need this simpler option using the users personal email.

import flash.events.MouseEvent;

import flash.net.URLRequest;

import flash.net.navigateToURL;

import com.adobe.images.JPGEncoder;

var bd:BitmapData = new BitmapData( 100, 100, false, 0x222222 );

var jpg:JPGEncoder = new JPGEncoder(50);

var ba:ByteArray = jpg.encode(bd);

emailButton.addEventListener(MouseEvent.CLICK, onClick);

function onClick(e:MouseEvent):void {

    var header:URLRequestHeader = new URLRequestHeader("Content-type", "image/jpeg");

    var request:URLRequest = new URLRequest("mailto:email?subject="+encodeURIComponent("Hello")+"&body="+encodeURIComponent("asdf"));

    request.requestHeaders.push(header);

    request.method = URLRequestMethod.POST;

    request.data = ba;

    navigateToURL(request," _blank");

}