Q: How do I modify the trust settings of the MIT CA file on Mac OS X?

Context

Initial testing of Mac OS X 10.5.7 has found an issue with how the operating system handles the MIT Certificate Authority (CA). In order to access secure portions of MIT websites, users installing the CA will need to modify the default trust settings associated with MIT CA. This is not necessary if the CA was installed prior to upgrading to 10.5.7.

Note: to make these changes, you will need administrative access to the machine.

Answer

1. Quit Safari if it is running.
2. Launch Keychain Access (/Applications/Utilities/Keychain Access).
3. Select System from the list of Keychains.
4. Double-click on MIT Certification Authority.
5. Click the triangle next to Trust.
6. Set "Secure Sockets Layer (SSL)" to "Always Trust".
7. Close the "MIT Certification Authority" window.
8. Enter the Mac's administrator name and password, and click OK.
9. Quit Keychain Access.