[Javascript] Read/write html tag contents with Netscape

[Paul]

I need to read & write the text contained by named html tags.

With recent Internet Explorers one can use innerText, i.e.: 

<td name="Tag4">The desired text to read & write</td> 
... 
function ReadWriteText(argTagName){ 
	alert(argTagName + ' contains ' + document.all.item(argTagName).innerText); 
	document.all.item(argTagName).innerText = "New contents"; 
} 

How can I do this with Netscape? Is there more than one method, depending
on Netscape/Javscript version? 

Thanks! 
Paul