Error in appache log

[sgrynd]

I am trying to track down why my graphs stopped working and have come across the following in my appache error log:

[Thu Sep 13 13:41:45 2007] [error] [client 10.128.60.62] PHP Notice: Undefined variable: svc in /usr/local/oreon/www/include/monitoring/engine/MakeXML.php on line 226, referer: http://usnjpar1nag01/oreon/oreon.php?p=2

[Thu Sep 13 13:41:48 2007] [error] [client 10.128.60.84] PHP Warning: filectime() [<a href='function.filectime'>function.filectime</a>]: stat failed for /usr/local/nagios/var/status.log in /usr/local/oreon/www/include/monitoring/engine/MakeXML4statusCounter.php on line 157, referer: http://10.128.57.139/oreon/oreon.php?p=5010110

[Thu Sep 13 13:42:00 2007] [error] [client 10.128.60.62] PHP Warning: filectime() [<a href='function.filectime'>function.filectime</a>]: stat failed for /usr/local/nagios/var/status.log in /usr/local/oreon/www/include/monitoring/engine/MakeXML.php on line 158, referer: http://usnjpar1nag01/oreon/oreon.php?p=2

[Thu Sep 13 13:42:00 2007] [error] [client 10.128.60.62] PHP Warning: filectime() [<a href='function.filectime'>function.filectime</a>]: stat failed for /usr/local/nagios/var/status.log in /usr/local/oreon/www/include/monitoring/engine/MakeXML.php on line 165, referer: http://usnjpar1nag01/oreon/oreon.php?p=2

Any help would greatly be appreciated.