Google Analytics and Oracle UCM - not playing nicely

Have had a couple of staff report this to me over the last week - but was having trouble replicating the problem. We have an A-Z button on our home page that had this link
http://www-public.jcu.edu.au/libcomp/az/index.htm?utm_source=LibcompHomePage&utm_medium=Button&utm_campaign=A2ZButton

I'm using GA to try and track the usage of the button to determine whether it's the best use of that screen real estate.  It's always worked but now it hides the jump to navigation and the dynamically created listing, showing only the H1

But if you remove the GA tracking code and go to http://www-public.jcu.edu.au/libcomp/az/index.htm it works just fine.  I've used lots of GA tracking on home page links for over a year now and I've never seen this behaviour before. Can't find a mention of it elsewhere in the blogosphere. I don't have time to play with it so all I can do is remove the tracking code and worry about it some other time. Would love to hear if anyone out there knows more.