Edit: this was a Visual Studio issue:
Although my Kendo grid renders fine in Opera and Chrome, all of a sudden it has gotten screwed up in IE9, after working fine for two days in IE9. And I've not changed anything! My CSS files and jquery files are all locally installed on my PC and haven't been touched.
I've been using Visual Studio, and running the page for two days straight, and stepping through code in the VS debugger. Sometimes the VS environment can get confused, so I shut VS down and reopened the project thinking that might help. I've also cleared IE browser cache. But no joy.
The weird thing, one moment the Kendo grid was rendering perfectly and the next moment its layout was hosed: the grid columns don't line up with the header cells, and the grid columns are all scrunched into about 60% width of the page, whereas the grid's header occupies the full 100% of the window. Also, if there's no value in a cell, the vertical grid line is not drawn that separates that cell from the one to its left. But as I said, it's working fine in two other browsers, and Opera for sure isn't using a cached version of the page because I hadn't tested it in Opera yet.
If you know what can cause this behavior, please advise.