var flag_loaded = false;

function preload() {
if (document.images) {
	one = new Array();
	one[0] = new Image(); one[0].src = "images/portfolio_on.gif";
	one[1] = new Image(); one[1].src = "images/company_on.gif";
	one[2] = new Image(); one[2].src = "images/enquiries_on.gif";
	one[3] = new Image(); one[3].src = "images/technical_on.gif";
	one[4] = new Image(); one[4].src = "images/mapbutton_on.gif";
	}
flag_loaded = true;
}

function swapButton( imgName, newImg ) {
	if ( ( document.images ) && ( flag_loaded ) ) {
		if (typeof(newImg) == 'string') {
			document.images[imgName].src = "images/" + newImg + ".gif";
			}
		else {
			document.images[imgName].src = one[newImg].src;
			}
	}  //end if
} //end function