SIGUSR1 received. Doing graceful restart?

[eva2000]

I just added some mod_rewrite directives to prevent hotlinking of my vbulletin forum\'s avatar and attachment file/dynamic urls.

When i checked my /usr/local/apache/logs/error_log (whm/cpanel based server), i had 100s of entries for web sites trying to hot link my images

now i found these entries in my error_log as well occuring every dozen or so lines
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[Mon Oct 15 12:37:59 2001] [notice] SIGUSR1 received. Doing graceful restart
[Mon Oct 15 12:37:59 2001] [error] Cannot remove module mod_log_bytes.c: not found in module list
[Mon Oct 15 12:38:00 2001] [notice] Apache/1.3.19 (Unix) mod_gzip/1.3.19.1a mod_bwlimited/0.8 PHP/4.0.5 mod_log_bytes/0.2 mod_frontpage/3.0.4.3 mod_ssl/2.8.1 OpenSSL/0.9.6 configured -- resuming normal operations

[Mon Oct 15 12:43:34 2001] [error] [client 216.140.23.66] script not found or unable to stat: /home/username/public_html/cgi-bin/clickresponder.pl

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what\'s SIGUSR1 received? and why is apache restarting itself?

Oh and i don\'t have any such script at home/username/public_html/cgi-bin/clickresponder.pl never did ... ever! so why is someone calling it?

thanks