ICal won't remember passwords correctly

Question

We're having problems with iCal not saving login information for subscribed calendars correctly.
At my workplace each employee publishes their calendars to a private server (Not MobileMe). Each employee then subscribes to the calendars of the other employees as needed.
The calendars are password protected. We maintain an internal web page with a list of the calendars available, and links that the employees can click on.
When adding a new calendar, a employee clicks on a link webcal://server/Calendars/name.ics in Safari, which causes iCal to launch an ask if you want to subscribe to the calendar.
After clicking subscribe, iCal asks for a username and password.
Then, you get the options window where you can choose a name for the calendar and set auto-update options and so on. The calendar has in the mean time been downloaded and is displayed in the background.
On the next refresh of the calendar, a warning sign appears next to the calendar.
At this point, a new entry has been added to the keychain. The address is http://server/Calendars/name.ics, and the username and password is correct as verified by using Apple's keychain tool.
Clicking on the warning sign in iCal results in a request for a username and password. The message is (translated to English) "Updating the calendar "Name" failed. The server rejected the username or password".
According to the server logs, it looks as if iCal tries to connect without a username and password after the calendar has been downloaded the first time.
I've found two solutions:
1. Change the address of the subscribed calendar to webcal://username@server/Calendars/name.ics
2. Click on the warning sign, and type in the username and password again.
#1 causes iCal to start using the keychain item added during the initial subscription to the calendar.
#2 causes iCal to add a second keychain item, with the address webcal://server/Calendars/name.ics
#2 also adds the username to the address of the subscribed calendar, so that the address becomes the same as in solution #1.
All our Macs (PPC/Intel) running Leopard 10.5.4 have this issue when adding new calendars.
Anyone experienced something like this?

Answer 1

If you are storing on your computer, arther than a sharing service, the issues are limited to your computer.
The most frequent problems are related to file permissions -- it cannot get the required permissions to store your preferences.
Run Disk Utility.
The most helpful operation Disk Utility does is ( Repair Disk ). That is a good idea. If you can only ( Verify Disk ) that is OK, as long as there are no un-fixable errors.
For this partiucular problem, you should also ( Repair Permissions ). It may list many messages, all of which can be ignored unless they appear in RED.