I read on some blogs that people are confused about the trackback support in dasBlog. Trust me, I am confused myself. I have implemented version 1.1 of trackback, using HTTP POST instead of version 1.0's HTTP GET and neglected supporting the 1.0 variant. That may be part of the problem. Still, I freely admit that trackback is probably one of the worst tested features of the whole code base in general. Getting that to work properly is on my list. Pingback works.