rem: var doDisable = !(enableHTTP11.selected && enableKeepAlive.checked); 
add: var prefString = enablePipelining.getAttribute("prefstring"); var isLocked =  parent.hPrefWindow.getPrefIsLocked(prefString);  var doDisable = !(enableHTTP11.selected && enableKeepAlive.checked) || isLocked; 
context: function checkPipeliningProxy(){  try {    var enableHTTP11 = document.getElementById("httpVersion11Proxy");    var enableKeepAlive = document.getElementById("enableKeepAliveProxy");    var enablePipelining = document.getElementById("enablePipeliningProxy");    var doDisable = !(enableHTTP11.selected && enableKeepAlive.checked);    enablePipelining.disabled = doDisable;  } catch(e) {}}
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/18a3e07505de1994c113beb812c351a126e95114/pref-http.js/buggy/suite/common/pref/pref-http.js