Pingbacks missing

Hello:

I have the option of “Allow link notifications from other Weblogs” activated, but since some time ago, (maybe because I have updated from 2.0.3 to 2.0.4) pingbacks to my site are not been generated.

If someone links any post to my site, or I link a post from other post, no any pingback is generated as a comment. I have been searching in the forums, but I have not been able of finding anything.

Thanks in advance,

Galder