Help! My WordPress Blog Contains 2,988 Categories

I recently translated a custom DB model to WordPress and it has the above mentioned number of categories.

When I go to MANAGE > CATEGORIES in order view my category list, after a few seconds of kaffufle the top of the page displays:

Fatal error: Maximum execution time of 30 seconds exceeded in /home/organic/public_html/wp-admin/admin-functions.php on line 579

I have checked this error out and most people seem to suggest it is an error with PHP. I have also looked on line 579 of the mentioned file and I found no PHP I see I can edit to prevent such an error occuring.

How do I increase the amount of time to display categories?