Oh, apparently this isn't a bug after all. whoo hoo!
MT-Blacklist -> Concatenation "error":
Use of uninitialized value in concatenation (.) or string at /some/path/to/extlib/File/Spec/Unix.pm line 78
Many people are reporting the “error” above. In fact, this a superfluous perl warning. It should affect absolutely nothing, and is in fact a bug (probably in MT) related to finding the plugin template files. Essentially MT tries several places to find the template files and if it doesn't find them, the warning from that attempt is written out to the browser. Eventually though, the MT-Blacklist templates are found as evidenced by the fact that you have a full working page in front of you.
You should completely ignore this warning. I will attempt to suppress it in the next version.
I'll have to donate some cash to Mr. Allen if this works as described.
