This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
It probably means that an iterate tag is not defined in the tld file. Out of band comment: if you are going to invest mindshare in general purpose tags, I'd focus on the JSTL (JSP Standard Tag Library) rather than a 3rd party library.