You all are using the wrong terms and confusing the heck out of me.
The permalink is used for pingbacks not track backs.
pingbacks happen automatically if you put a link in the body of the post.
trackbacks are placed in the trackback box and are not the other sites permalink. you need to click on trackback to usually see the trackback url for that site. It will say the track back url for this site is:
You cannot turn off track packs only pingbacks, and that box did not function on my WP, I had to fix 2 files to enable me to turn it off.
The track back for your blog is the permalink then add /trackback/ on the end. You can test to your own site there is no reason to use any other site for testing. just pingback or track back to one of your own posts. If you enable your logs you can see what is and is not happening.
since there are so many different problems with these functions I came across this in the codex which may or may not help.
go to the bottom and read about the .htaccess file.
This has to be sever related or possibly sub-version related. Since mine all work, and I have 1.5.
My probelm was my server did not have mod_rewrite installed and enabled.
Also I dislike pingback and could not turn it off, but it turned out to be hard coded on in 2 files that I had to edit and now it is off.