Simple example using webdav

Hi,

I'm trying to understand how online commenting works with a webdav folder, in a basic situation :
I have a pdf and a fdf file (on my desktop) named "revisable.pdf" and "test.fdf".
A webdav folder is set at : http://localhost/webdavtest/ (accessible via IE, read-write access to anyone on the local folder "webdavtest").
A website "webdavtest" exists and, via IIS, I have set read/write/explore permission and anonymous acces as Administrator.

In the fdf file :
...
/F(revisable.pdf)
...
Collab.defaultStore = "DAVFDF";
Collab.setStoreSettings("DAVFDF", "http://localhost/webdavtest/");
...

When I open the fdf file, I see the pdf in adobe reader, a warning message appears (like "your online comment preferences are been accessed. Continue?"). I click "yes". The "comments and annots" toolbar appears, but WITHOUT the button "Send/Recieve comments".

I tried to replace "localhost" with my local IP and with my computer name, to use adobe acrobat instead of adobe reader etc... Nothing works.

Did I forget something that allows reviewing to be activated?

Thanks.

ps : the fact that adobe doesn't provide any useful error message is very annoying.