Window.open With Url Variables?

i have this code:

echo "<script type='text/javascript'>openWindow('".$adress."')</script>";

the $adress send an url with variables like "xpto.com?var=1&varB=2"

Problem is that using window.open always encodes & character to & and the url doesn't open. I have tried many functions but still doesn't work.I have this javascript code:

function convert(str)
{
str = str.replace(/&/g,"&");[code].....

The convert function doesn't do anything. the commented javascript functions like unescape, etc also doesn't work. If i do alert(adress) it converts & to & but if i do document.write(adress); it shows correctly. So i assume that some functions encode and others don't. Meaning that window.open encode by default. It there a way to override this?