Hi Pedro!
Thanks for your translation!
QUOTE(Pedro @ Aug 8 2007, 20:34)

I tried to add a new event but the new calendar created is only readable. I tried to change this option from the calendar properties but the new calendar is always set as Read-only

This is intentional (kind of). For the moment, the extension is not bidirectional, i.e. it can display existing birthdays as events, but not modify them or create new ones. That's the reason why it is set to read-only and why this cannot be changed. Maybe the extension will provide bidirectional access to the addressbook in future versions...
QUOTE(Pedro @ Aug 8 2007, 20:34)

I installed Lightining, MoreColsForAdressbooks and then ThunderBirthDay. I set a birthday for a casual contact in my address book then I created a new calendar with your extension.
I opened the new birthday calendar, and I went to the date of the birthday searching the new event but nothing happened.
This, of course, is not intentional! You installed the right extensions and used the extension like it is meant to (as far as I can tell). The only things I can think of you might have done wrong is
* to choose the wrong address book when creating the calendar or
* to entere an invalid date (numbers only: 1<=month<=12, 1<=day<=31, 0<=year<=3000)
If none of this is the problem, this might be an unknown bug. In this case, I'd love to know its reason! A possible way to find it, is to increment verbosity like this:
* rename the .xpi-file to a .zip file and extract it
* open /js/calThunderBirthDay.js and go to the very end of the file
* change the 5 in "if (aDebugLevel >= 5) {" to a 4 (then 3,2,1...)
* repack the modified files to a zip, rename it to .xpi and install the new version
* go to lightning where the birthday events should appear, then open the error console
* look for suspisous lines beginning with "TBD:" (at debuglevel 1, there should be a lot of them, at level 0 more than you can ever read

)
So far, I don't know what to tell you to look for, as it works on every machine I am able to test it. If you discover anything suspisous, please let me know.
I hope this helps! Greets, Ingo
Edit1:I forgot one thing, that might be the reason: if you first created the calender and then added the birthday to the addressbook contact, the birthday doesn't appear immidiately in lightning. First, the calendar has to be reloaded, which happens automatically at startup and then every 30 minutes. You can force a reload by right-clicking on a calendar in the calendar list in lightning and then choosing "Reload external calendars" in the context menu.
Edit2:I have to admit, that the reason is indeed a bug, but the good thing is, that I can reproduce it. It occures when there are only a very few contacts with birthdays. Until I released a new version, I can only advise you, to add more birthdays to your addressbook

Thanks a lot for indicating that issue!!