var namesVec_d = new Array("exportacao_bt4_1.gif", "exportacao_bt4.gif");
var root='images/';

function toggle_d(image,showorhide){
if (showorhide=="show") {image.setAttribute('src',root+namesVec_d[0]);}
if (showorhide=="hide") {image.setAttribute('src',root+namesVec_d[1]);}

nr = image.getAttribute('src').split('/');
nr = nr[nr.length-1]

if(nr==namesVec_d[0]){image.setAttribute('src',root+namesVec_d[1]);}
else{image.setAttribute('src',root+namesVec_d[0]);}

}