File transfers with Webdav in Exodus 0.9

Hello,


I use Exodus as a Windows client for a Jabber server (jabberd) on Linux
(Debian Woody). We use Exodus on different locations, across firewalls
and ADSL routers and over a SSL link and everything is working
beautifully -- except file transfers.

I'm trying to puzzle this out. Since we already have an Apache server
with the Dav module, I decided to use the Tools > Options > File
Transfers > "Use a Web server to host the files which I send" option.

So I set up a Dav shared directory on Apache. I know it's working
properly because I tested it with the Linux client "cadaver". Both users
who tested file transfer have write access to this Dav directory. They 
can also browse its content using a Web browser.

I tested file transfer locally, running two instances of Exodus on the
same computer. It worked fine.

However, file transfer fails between users on different locations and
behind firewalls. I suppose routers (with NAT) and/or firewalls are
interfering, but I cannot find any trace in the firewall logs.

=> Could you explain briefly how file transfer is supposed to work when
using the Web server option? I'm trying to understand which ports need
to be opened in firewalls.

I thought that only ports 5223 (Jabber over SSL) and 443 (HTTPS) would
need to be opened: both Exodus clients could share file location
information over the Jabber link and then issue a Dav PUT or a GET
request to  exchange the actual file. I'm wondering whether I missed
something.


Thanks.

Alexandre Ratti