Ok, what phone do you have and how did you update (official over the air update, custom ROM, or other)? Either should have updated the kernel, unless you have one of those unusual devices where it needs to be flashed separately, but a ROM Update wouldn't update other parts of the firmware. So if we know how you updated it we'll be able to eliminate some possibilities.
If it was an official update I'd suggest backing up and doing a factory reset. If it was a custom ROM you presumably did that when you installed it - if not then you should, as that could be the cause here.