Oh, så snart jeg poster her, er der svar i den anden tråd. Fik hjælp derfra, så det virker nu ;-) Lækkert. I kan se tråden her (
http://www.webmasterworld.com/forum91/2789-1-10.htm#msg6), men quoter ham lige.
Three small things:
1. The arguments are separated by a semicolon ';' in the function call. Should be a comma.
2. For the update to be really 'live', you need to use the onKeyUp event handler. onchange only fires when the textarea loses focus.
So..
onKeyUp="LiveUpdate(this,document.getElementById('LiveDisplay'))"
3. To replace all instances of \n in the value string you need to use a regular expression with the 'g' modifier (global) as first arg.
dest.innerHTML = source.value.replace(/\n/g,"<br>");
That should now work.