Mine

<html>
<head>
<title>disable</title>
</head>
<body>
<form>
<input type="checkbox" name="imgs[]" value="1" id="e1"/>
<input type="checkbox" name="imgs[]" value="2" id="e2"/>
<input type="checkbox" name="imgs[]" value="3" id="e3"/>
<input type="checkbox" name="imgs[]" value="ALL" id="e_all" onclick="disableOthers(this);"/>
<script type="text/javascript" language="javascript">
function disableOthers(all) {
  //for(var el in document.getElementsByTagName("input")) {
  els = document.getElementsByTagName("input");
  for(i = 0; i < els.length; ++i) {
    if(els[i].type == "checkbox" && els[i].name == "imgs[]" && els[i].value != "ALL" && all.checked) {
      els[i].disabled = true;
    } else {
      els[i].disabled = false;    
    }
  }
}
</script>
</form>
</body>
</html>