Duplicate entries in ping services (weblogs) after publishing post

HI,

when i publish post, i use to update pingomatic then further pingomatic pings various services like weblogs, feedburner, google blog search etc.

My problem is that Recently i have noticed in weblogs changed log file after downloading it that my domain name appears 2 times for the same post after publishing within interval of 2-10 second, one with trailing slash and one without trailing slash and that basically leads my domain to excess ping penalty.

I have checked with my other website and everything seems to be working fine on them, except one which is my main website.

I have also tried to ping directly weblogs (http://rpc.weblogs.com/RPC2) from withing wordpress installation. But found the same problem.

So far i have tried following :

1. Reinstalled wordpress

2. cleaned up options table completely and disabled all plugin to check the issue.

3. Same DB tested with the other domain and this seems to working fine.

So if any one guide me to troubleshoot the problem it will be helpful for me.

thanks.