IE4 = (document.all) ? 1 : 0;
NS4 = (document.layers) ? 1 : 0;
ver4 = (IE4 || NS4) ? 1 : 0;

currentX = currentY = 0;
whichEl = null;	   
	    
function grabEl(e) {
    if (IE4) {
        whichEl = event.srcElement;
	    
        while (whichEl.id != activeEl.id) {
            whichEl = whichEl.parentElement;
            if (whichEl == null) { return }
        }
    }
    else {
        mouseX = e.pageX;
        mouseY = e.pageY;
	    
        for ( i=0; i<document.layers.length; i++ ) {
        tempLayer = document.layers[i];
            if ( tempLayer.id != activeEl.id) { continue }
            if ( (mouseX > tempLayer.left) && (mouseX < (tempLayer.left + tempLayer.clip.width)) 
                 && (mouseY > tempLayer.top) && (mouseY < (tempLayer.top + tempLayer.clip.height)) ) {
                whichEl = tempLayer;
            }
        } 
	    
        if (whichEl == null) { return}
    }
	    
    if (whichEl != activeEl) {
        if (IE4) { whichEl.style.zIndex = activeEl.style.zIndex + 1 }
            else { whichEl.moveAbove(activeEl) };
            activeEl = whichEl;
    }
	    
    if (IE4) {
        whichEl.style.pixelLeft = whichEl.offsetLeft;
        whichEl.style.pixelTop = whichEl.offsetTop;
	    
        currentX = (event.clientX + document.body.scrollLeft);
        currentY = (event.clientY + document.body.scrollTop); 
	    
    }
    else {
        currentX = e.pageX;
        currentY = e.pageY;
	    
        document.captureEvents(Event.MOUSEMOVE);
        document.onmousemove = moveEl;
    }
}
	    
function moveEl(e) {
    if (whichEl == null) { return };
	    
    if (IE4) {
        newX = (event.clientX + document.body.scrollLeft);
        newY = (event.clientY + document.body.scrollTop);
    }
    else {
        newX = e.pageX;
        newY = e.pageY;
    }

    distanceX = (newX - currentX);
    distanceY = (newY - currentY);
    currentX = newX;
    currentY = newY;
	    
    if (IE4) {
        whichEl.style.pixelLeft += distanceX;
        whichEl.style.pixelTop += distanceY;
        event.returnValue = false;
    }
    else { whichEl.moveBy(distanceX,distanceY) }
}
	    
function checkEl() {
    if (whichEl!=null) { return false }
}
	    
function dropEl() {
    if (NS4) { document.releaseEvents(Event.MOUSEMOVE) }
    whichEl = null;
}
	    
function cursEl() {
	if (IE4) {
		if (document.readyState == 'complete') {
			if (event.srcElement.id == activeEl.id) {
				event.srcElement.style.cursor = "move"
			}
		}
	} if (NS4) {
		if (event.srcElement.id == activeEl.id) {
			event.srcElement.style.cursor = "move"
		}			
	}
}

function moveElTo(x, y) {
	 if (IE4) {
        activeEl.style.pixelLeft = x;
        activeEl.style.pixelTop = y;       
    }
    else { activeEl.moveTo(x, y) }
}
	    
if (ver4) {
    if (NS4) {
        document.captureEvents(Event.MOUSEDOWN | Event.MOUSEUP);                      
    }
    else {
        document.onmousemove = moveEl;
        document.onselectstart = checkEl;
        document.onmouseover = cursEl;                     
    }
	    
			
    document.onmousedown = grabEl;
    document.onmouseup = dropEl;
}