Unusual Apache error_log entries

Question

My Apache error_log (and my wife's) are full of these:
[Mon Feb 04 13:19:31 2013] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/crls
[Mon Feb 04 13:19:31 2013] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/crls
[Mon Feb 04 13:19:31 2013] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/crls
[Mon Feb 04 13:27:56 2013] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/crls
[Mon Feb 04 13:27:56 2013] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/crls
They seem to appear randomly. We've wondered whether it was Safari, Versions or something else causing them, but they appear even when those are quit.
Sometimes they're a bit different:
[Fri Aug 17 15:09:05 2012] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/ThawtePremiumServerCA.crl
or:
[Thu Aug 23 08:51:07 2012] [error] [client 127.0.0.1] File does not exist: /Library/WebServer/Documents/SVRSecureG3.cer
They've appeared for as long as I can remember (so probably from Snow Leopard onwards) and they drive us a bit crazy!
It's just one of those things that's always been annoying and it'd be wonderful if someone out there knew what the issue was.
Many thanks in anticipation!

Answer 1

Thanks very much for the reply.
No luck though - those commands didn't seem to do anything.
One odd thing is that, when I restart Apache, it does take a while before the errors start appearing again.
They also happen when I'm not using it so it must be something the machine's doing in the background.
Just noticed I posted this reply using my developer account, hence the different profile name!
Message was edited by: mrmuppet