AJAX: Works with div but not textarea

I am using SACK for AJAX support.
http://www.twilightuniverse.com/projects/sack/

I need to populate an empty textarea from the server with AJAX.

The code works perfectly at placing content inside a div:
http://fds2432.googlepages.com/demo_div.html

But it does not work well when used with a textarea:
http://fds2432.googlepages.com/demo_textarea.html

Some browsers work with both but Opera and old Mozilla like the div version but not the textarea version.

Any ideas?

Thanks!
demo-div.html.txt
demo-textarea.html.txt