Youtube API PHP problem

I downloaded the library Yotube API PHP (search for videos) from zend.com and its examples. On windows (localhost) everything works fine ... Uploading on the debian server, and there at the request search video gives an error:

Invalid response received - Status: 404

Code of this error from videO-browser.js

/**
 * Sends an AJAX request to the server to retrieve a list of videos or
 * the video player/metadata.  Sends the request to the specified filePath
 * on the same host, passing the specified params, and filling the specified
 * resultDivName with the resutls upon success.
 * @param {String} filePath The path to which the request should be sent
 * @param {String} params The URL encoded POST params
 * @param {String} resultDivName The name of the DIV used to hold the results
 */
ytvbp.sendRequest = function(filePath, params, resultDivName) {
  if (window.XMLHttpRequest) {
    var xmlhr = new XMLHttpRequest();
  } else {
    var xmlhr = new ActiveXObject('MSXML2.XMLHTTP开发者_运维技巧.3.0');
  }

  xmlhr.open('POST', filePath, true);
  xmlhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded'); 

  xmlhr.onreadystatechange = function() {
    var resultDiv = document.getElementById(resultDivName);
    if (xmlhr.readyState == 1) {
      resultDiv.innerHTML = '<b>Loading...</b>'; 
    } else if (xmlhr.readyState == 4 && xmlhr.status == 200) {
      if (xmlhr.responseText) {
        resultDiv.innerHTML = xmlhr.responseText;
      }
    } else if (xmlhr.readyState == 4) {
      alert('Invalid response received - Status: ' + xmlhr.status);
    }
  }
  xmlhr.send(params);
}

Bad english, sorry

Apperently, your request string is somehow wrongly transmitted (Error 404 = Ressource not found). You want to check what exactly is different between your local copy and the server copy by using echos for debugging and the right places.