This version is IE only (well the code that I dished out was) however here is a solution so that the document.getElementById works on browsers that don't support it 
the solution
The following bit of script checks to see if document.all is present, but document.getElementById is not. If this is the case it then assigns a new function to document.getElementById that wraps around document.all
if(document.all && !document.getElementById) {
document.getElementById = function(id) {
return document.all[id];
}
}
With this script present at the top of the head section, either in an external file or an inline script, all that is needed to reference an element on IE, Mozilla/NS6.x and a number of other browsers is document.getElementById('theID')
Hope that helps if your trying to make it netscape compatiable !!!