Hey Jason, thanks for the response.
I already have the link you refer to bookmarked and know about the default panel setting; however this does not apply in my case as those panels are dynamic and the number of them is not constant hence my use of "Accordion1.openLastPanel" which works perfectly in Chrome.
I'm not tech savvy enough to know why it does not work in IE/FF or how to code a similar fix for them or who or where I should ask. Any leads are appreciated.