jQuery Grid Plugin - jqGrid

I have a grid that accesses json formatted data via an ajax call to a servlet routine. The first issue I had is that I have several values on the page that, when changed, should result in the grid being updated with the changed data.  When I called the function I wrote to reload the data, the servlet routine wasn't ever invoked, even though I could see the js function being called in debug.  I discovered the solution was to use the .trigger(”reloadGrid”) method and now the servlet was being invoked again.  All was well.

But the data returned from the servlet was the same data, so I checked the URL that was being passed in the grid.  In debug, the ajax url in the grid appears to be changed (I can see all the new values) but when it is passed to the servlet, the url appears to be unchanged (at least the parameters aren't changed although they ARE changed in the url that is invoked)

So the question is: Does jqGrid 'cache' the ajax call?  If so, can this behavior be changed?  If NOT, where should I look to see where the url is perhaps being cached.

Thanks

Follow up:

Further debugging of the grid.base.js shows that the at line 93 the value of the url found in p.url IS correct but when the json string is executed in line 831, the value of p.url and ts.p.url has reverted BACK to it's original value. So, somewhere in the code the correct value is being replaced by a cached value.  I don't know enough about jQuery to walk through all the code but something isn't quite right here.

Suggestions?