[jQuery] cluetip with dynamic data from textarea

[Margie]

I am using the cluetip plugin to show a formatted version of text that
the user types into a text area.  So I have a <textarea
id="description">, and as the user types, they can at any time click a
"preview" button will call cluetip to display the popup.  Here is my
current cluetip call:

$('#id_preview_link').cluetip(
 {
   ajaxSettings: {dataType:'html',
                  type:'POST',
                  data:{'markup':$('#id_description')}
                 }
 }
)

When I click my preview button to activate the clutip, the post data
that is sent is whatever was in #id_description at the type the cluetip
() code above was executed.  IE, it doesn't post the current value
that's in #id_description.

Can anyone tell me how to make the activation of the cluetip send the
current text that is in my #id_description field?

Thanks very much,

Margie