The first integration technnque in OBIEE Presentation Service is the use of HTML Markup and then of javascript.
You can add HTML content :
If you want to be able to add HTML markup in other fields, you have to disable HardenXSS.
To check your privileges :
If you don't see the check box, you can try to add a node <HTML></HTML>.
For example with a javascript code :
<HTML>
<A HREF='javascript:onClick=alert("Not an active link")'>Click here</A>
</HTML>
Tested with version 10.1.3.4 and doesn't work.