This week's book giveaway is in the Performance forum. We're giving away four copies of The Java Performance Companion and have Charlie Hunt, Monica Beckwith, Poonam Parhar, & Bengt Rutisson on-line! See this thread for details.
It's bad practice to have any Java code in your JSP. Or is he saying that JSP tags should not reference objects that happen to be Hibernate POJOs? (I think the later is fine so long as you have disconnected them from the database.)