I am reposting this:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.2)
Gecko/20060308 Firefox/1.5.0.2
and
Plugin Java(TM) 2 Platform Standard Edition 5.0 Update 6
Note: This does not happen with: Java(TM) 2 Platform Standard Edition
5.0 Update 5 or older.

>

Example: Installing ipp://9.26.192.23/ipp/PRT-HP-IIISi-PAL...

You will have to hit the back button several times, close the browser or
goto another page.