Pings not back

I seem to be having trouble with my installation of WordPress sending out pings to other sites, and also using the Ping-o-matic and Technorati RPC service.

This is becoming a nuisance, as every time I post (which has been becoming gradually more frequent lately), I have to manually ping Technorati.

I have refrained from using other blog services so far, I imagine manually pinging around 50 sites manually might get annoying.

So, I’ll have to have a play and see how I get. If anybody has any thoughts, I’d appreciate it.