vb.org Archive - What would this be from in the error log?

I have little knowledge, so if this is simple then feel free to give me flak, haha.

I found this and it appears often in our error log:

Code:

[Thu Mar 16 01:00:21 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_warns.php on line 31

[Thu Mar 16 01:00:07 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_alerts.php on line 33

[Thu Mar 16 01:00:05 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_bans.php on line 30

[Thu Mar 16 00:59:06 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_warns.php on line 31

[Thu Mar 16 00:59:05 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_alerts.php on line 33

[Thu Mar 16 00:59:03 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_bans.php on line 30

[Thu Mar 16 00:58:19 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_warns.php on line 31

[Thu Mar 16 00:58:18 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_alerts.php on line 33

[Thu Mar 16 00:58:07 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_bans.php on line 30

[Thu Mar 16 00:57:13 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_warns.php on line 31

[Thu Mar 16 00:57:12 2006] [error] PHP Fatal error:  Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_alerts.php on line 3

[Thu Mar 16 00:57:03 2006] [error] PHP Fatal error: Call to a member function on a non-object in /home/hondaacu/public_html/forums/includes/cron/kill_bans.php on line 30

We are currently using Inferno Warning System v1.3.

I looked in these files and the error'd files say vB3 Warn System V1 By Zero Tolerance.

Why would vB be calling to these files?

X vBulletin 3.8.12 by vBS Debug Information
Page Generation 0.01133 seconds Memory Usage 1,719KB Queries Executed 10 (?)
More Information
Template Usage: (1)ad_footer_end (1)ad_footer_start (1)ad_header_end (1)ad_header_logo (1)ad_navbar_below (1)bbcode_code_printable (1)footer (1)gobutton (1)header (1)headinclude (6)option (1)post_thanks_navbar_search (1)printthread (1)printthreadbit (1)spacer_close (1)spacer_open Phrase Groups Available: global postbit showthread	Included Files: ./printthread.php ./global.php ./includes/init.php ./includes/class_core.php ./includes/config.php ./includes/functions.php ./includes/class_hook.php ./includes/modsystem_functions.php ./includes/class_bbcode_alt.php ./includes/class_bbcode.php ./includes/functions_bigthree.php Hooks Called: init_startup init_startup_session_setup_start init_startup_session_setup_complete cache_permissions fetch_threadinfo_query fetch_threadinfo fetch_foruminfo style_fetch cache_templates global_start parse_templates global_setup_complete printthread_start bbcode_fetch_tags bbcode_create bbcode_parse_start bbcode_parse_complete_precache bbcode_parse_complete printthread_post printthread_complete
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