Update for Firefox 4.0 Rated 5 out of 5 stars

1. Download "Peraperakun2.1.xpi" from http://downloads.mozdev.org/peraperakun/Peraperakun2.1.xpi (right click; save link as; and select a destination folder).
2. Open the ".xpi" file (double clic) > "Select a program from a list of installed programs" > select "WinRAR archiver" > unmark "Always use the selected program to open this kind of file" > "Ok"
3. Open the file "install.rdf" (double clic) > "Select a program from a list of installed programs" > select "Notepad" > unmark "Always use the selected program to open this kind of file" > "Ok"
4. In "<!-- Firefox -->", edit the "maxVersion" line from 3.* to 4.*: <em:maxVersion>4.*</em:maxVersion>
5. In Notepad: "File" > "Save"
6. In WinRAR: "File install.rdf was modified. Do you..." > "Yes"
7. Close Notepad and WinRAR.
8. Repeat exactly the same for the dictionary ("Chinese-English Dictionary" in my case)
9. Go to Firefox > "Add-ons" > "Extensions" > Remove "Perapera-kun" and "dictionary".
10. Drag and drop the news ".xpi" files to Firefox.
11. Install the extensions and restart Firefox.
12. Voila!

This review is for a previous version of the add-on (2.1.1.1-signed).