Apple Final Cut Pro v3.0.1 Update for X

is available for download from Apple's server. From the Read Me file,

Use this Updater to prevent the following:

Some dual processor computers may unexpectedly quit when Final Cut Pro 3.0 is installed on Mac OS X. Final Cut Pro 3.0 will unexpectedly quit when you open it if the Internet System Preference pane only contains partial information. This problem can occur on both single and dual processor computers. This Updater will prevent this problem from occurring, but it will not add information to the Internet System Preference pane.

This Updater is for Final Cut Pro 3.0 on Mac OS X only; it is not required for Mac OS 9. There are four versions of this Updater. You must use the one that corresponds to the version of Final Cut Pro 3.0 you have. You can tell which version of Final Cut Pro 3.0 you have by checking the name of your Final Cut Pro 3.0 CD. The four versions of the Final Cut Pro 3.0 Updater are for the following versions of Final Cut Pro:

Final Cut Pro 3.0 and the Final Cut Pro 3.0 Upgrade
Final Cut Pro 3.0 Not for Resale (NFR)
Final Cut Pro 3.0 Academic
Final Cut Pro 3.0 Academic Lab