function showDiv(div_id) {  
	var style_sheet = getStyleObject(div_id);
	if (style_sheet)
		changeObjectVisibility(div_id, "block");	  
	else {
		//alert("Sorry, this only works in browsers that support Dynamic HTML");
	}
}

function hideDiv(div_id) {
	var style_sheet = getStyleObject(div_id);	  
	if (style_sheet)
		changeObjectVisibility(div_id, "none");	  
	else {
	//alert("Sorry, this only works in browsers that support Dynamic HTML");
	}
}

function getStyleObject(objectId) {
	// checkW3C DOM, then MSIE 4, then NN 4.
	if(document.getElementById && document.getElementById(objectId)) {
		return document.getElementById(objectId).style;
	}	
	else if (document.all && document.all(objectId)) {  
		return document.all[objectId].style;
	}   
	else if (document.layers && document.layers[objectId]) { 
		return document.layers[objectId];
	}   
	else {
		return false;
	}
}

function changeObjectVisibility(objectId, newVisibility) {
    // first get the object's stylesheet
    var styleObject = getStyleObject(objectId);
    /* then if we find a stylesheet, set its visibility
       as requested */
    if (styleObject) {
		styleObject.display = newVisibility;
		return true;
    }    
    else {
		return false;
    }
}