In my Apache access log I have more than 10 million of such queries:
::1 - - [21/Nov/2011:16:15:54 +0000] "OPTIONS * HTTP/1.0" 200 - "-" "Apache/2.2.15 (Unix) PHP/5.2.13 (internal dummy connection)"
Is it due to the mod_rewrite redirects or what? Why are they shown in the IPv6 notation? Let me know if you require more info on the server configuration. I use Debian 5.0.