echo is printing two extra characters

Hi,

I have a simple php script:

    <?php
        // thePhpScript.php
        echo "hello";
    ?>

I am calling it from a javascript function vis a vie some ajax stuff like so:

    <script>
    function callScriptAJAX() {
        httpObj.open("GET", "thePhpScript.php", true);
        httpObj.onreadystatechange = handleHttpResponse;
        httpObj.send(null);
    }


And then I try to print the response like so:

    function handleHttpResponse() {

        if (httpObj.readyState == 4) {
            alert("[" + httpObj.responseText + "], length is: " + httpObj.responseText.length);
        }
    }    
    </script>

But the response printed in my message box is always:

    [
     hello], length is: 7

Why is my php script returning a carriage return and a white space before the word 'hello'!? It's driving me crazy. I thought it would print back perfectly [hello], length is 5.

Please let me know what I'm doing wrong, thanks!