[solved!] How do I get a textarea's cursor (caret) position?

I want to add a quick reference system to my procedural generator scripting engine. Functions in the script are called line-by-line, so if I can determine the cursor's position in the scripting textarea, I can provide accurate and relevant tooltips etc. I know the javascript properties selectionStart and selectionEnd can be used to retrieve this - but I've had no luck. Any ideas?

Self-solved! First bit of javascript I sorted out for myself...

Browser.ExecJS

( "{ var ctl = document.getElementById('code');

var startPos = ctl.selectionStart;

var endPos = ctl.selectionEnd;

startPos + "","" + endPos; }" )

Where "code" is the ID of the textarea, in my case... note the double ""s!