Rated 3 out of 5 stars

le mi_ve ar Aib. 24, 2009 · buan-nasc

Here is a different extension that changes the reply quote format:
http://nic-nac-project.de/~kaosmos/changequote-en.html

It suits my needs better. One bad point of that one though: you can't customise the date format as detailed as in the current extension.