Getting binary data. Lost of 128+ chars

[Escain]

Hello!

I am trying to download an image by ajax (for some reasons i will not explain here).
But i am getting all 127-255 bytes seted to 65533.
Example:
From the image

66 77 54 16 0 0 0 0 0 0 54 0 0 0 40 0 0 0 32 0 0 0 32 0 0 0 1 0 32 0 0 0 0 0 0 0 0 0 19 11 0 0 19 11 0 0 0 0 0 0 0 0 0 0 255 255 255 0 255 255 255 0 0 0 0 28 0 0 0 65 0 0 0 37 135 135 135 0 145 145 144 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.....

i get

66 77 54 16 0 0 0 0 0 0 54 0 0 0 40 0 0 0 32 0 0 0 32 0 0 0 1 0 32 0 0 0 0 0 0 0 0 0 19 11 0 0 19 11 0 0 0 0 0 0 0 0 0 0 65533 65533 65533 0 65533 65533 65533 0 0 0 0 28 0 0 0 65 0 0 0 37 65533 65533 65533 0 65533 65533 65533 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0....

I don't understand why that occur and i cannot use server-side base64 encoding.

Here the code i am using:

		http = new XMLHttpRequest();
		http.onreadystatechange = new Function("",
		"callbacksend('"+url+"');");
		http.open("post", "http://www.myserver.com/Icon.bmp", true);
		http.setRequestHeader("Accept-Charset", "utf-8");
		http.send(null);

function callbacksend(url){
	if(http.readyState == 4){
		if(http.status == 200){
			// todo ok
			for( var i=0; i < 100; i++){
				document.body.appendChild(document.createTextNode(" " + http.responseText.charCodeAt(i)));
			}			
		}
	}
};

Thx for any help and sorry for my poor english

Escain