CCNA, CCNP, MCSA, CCNA Final Exam, All Answer Test Module With 100/100

I am using the slimScroll plugin for jQuery by Piotr Rochala Which is a great plugin for nice scrollbars on most browsers but I am stuck because I am using it for a chat box and whenever the user appends new text to the boxit does scroll using the .scrollTop() method however the plugin's scrollbar doesnt scroll with it and when the user wants to look though the chat history it will start scrolling from near the top. I have made a quick demo of my situation http://jsfiddle.net/DY9CT/2/ Does anyone know how to solve this problem?

Am trying to get this code <iframe src="http://www.play-asia.com/paOS-38-19-0,,none,0,0,0,0,trans,000000,left,0,0-49-en-76-5-70-dhf7-6-2-78-2i-90-f8z9-33-iframe_banner-40-6-44-100%2525.html" style="border-style: none; border-width: 0px; border-color: #FFFFFF; padding: 0px; margin: 0px; scrolling: vertical; frameborder: 0;" scrolling="vertical" frameborder="0" width="100%25" height="1428"></iframe> To fill the page (height wise) and also without the scroll bar ive tryed and tryed to use css without any luck Anyone have any ideas how/if I do do this? Thanks