I now tested it with another BLOG using s9y and it worked!

Can anyone tell me what is wrong with that article, so that I cannot send a trackback ping to it:

http://www.lawblog.de/index.php/archive ... -springer/

???

Me again:

I did also install the serendipity_event_trackback plugin and tried to manually enter a trackback, which did not work either...

Yes, I did.

Let me show an example:

I want to send a trackback ping for this article:
http://www.lawblog.de/index.php/archives/2005/05/02/post-fur-springer/

http://www.lawblog.de/index.php/archives/2005/05/02/post-fur-springer/ is also the URL I use in my own article.
I also tried
http://www ...

Yesterday I installed s9y and like it very much. But there is one Problem:

When sending a trackback ping to my own articles (for instance a trackback to an article I wrote yesterday) everything works fine.

When sending a trackback to an extern URL, nothing works. I alway get the message "Trackback ...