Thunderbird 5.0 -> QuickText extensions does not work

I installed Thunderbird 5.0 on my OpenIndiana Box from the reference page in

In former releases of Thunderbird, I used a lot the quicktext-extension.
This extension allows to define macros/templates of text, which can be
expanded after pressing a special key like TAB in my case.
But the extension does not work anymore with Thunderbird 5.0.
Also editing the install.rdf and increasing the version number does not solve
the problem.

But at the home of the developer I found a beta version for download.
This extension also works in thunderbird 5.0 and all my templates are
here again.