The problem I was having with Internet Exploder turns out to be unrelated to jqGrid.
Apparently there is an undocumented “feature” of exploder that limits the number of CSS and Javascript files you can reference in the container of a HTML page.
Thanks for the fix, that does indeed address the error that shows up on the console in Safari (and appears to also fix the problem I saw with firefox and the y[0] is undefined.
However, the grid still isn't working.
Go to the URL and login as detailed above using safari.
I don't know if this is more information or not, but in the event that I do get a pension added (which happens occasionally, leading me to believe there is some kind of timing problem inside jqGrid when dealing with Safari/Chrome/IE7/IE8's object model) if I then select the pension and try to edit it by clicking the pencil icon, the editing modal pops up, but if I click save or cancel, nothing happens.