Apple released OS X 10.3.8 on Wednesday. As usual there are a few reports of update problems. I usually wait a couple of days to install a new update to see if the install issues are isolated or the result of an improper installation or a real problem. They usually ferret themselvs out in a few days if they are real problems. That said, I’ve never had a problem updating using “Software Update”. I do repair the disk and permissions before an installl and then permissions again after the update. (Disk Utility).
If you want to directly download the file do it here: OS X10.3.8 Update (27.7MB).