When turtle was written some assumptions were made about the ip addresses
of the people running it. In particular you need to be able to receive incoming
connections on port 1391, in order for others to connect to you.
This can be done easily by setting a port forwarding (open a port) in your nat 
or firewall, if you are behind one. This is not always possible due to the fact 
that sometimes you don't have the priviledges or ability to do so, for example 
when behind a corporate firewall.
The new version of Turtle include a library called XSTUNT, that will try to
establish a connection anyway, even when you and your friend, are not reachable
on port 1391. This is done by registering to a central "helper node" that will
coordinate the job and try to establish a direct connectioni between you and your
friend. This doesn't mean that your data will be realayed throgh a third party
server, but only that an attempt of direct connection will be tried.
Please note that this is only a best effort library, it doesn't guarantee
that a connection will be establish.

You can also run your own "helper node", you can obtain the sources at:
http://www.cis.nctu.edu.tw/~gis87577/xDreaming/XSTUNT/Source/server.zip
and by following the instruction in the zip file.
To point your Turtle to this new server you need to override the default one
by placing a text file called xserver.conf in /tmp containing as only
text the two ip addresses of your server separated by a space.
Es: 130.37.26.4 130.37.26.5

Due to the limit of resources available, like different machines, behind
different middleboxes, extensive testing couldn't be performed.
If you experience any trouble, please signal them in the newsgroup:
http://groups.google.com/group/turtle-p2p

In case you are experiencing serious troubles with the new version, you can
revert to the 1.0 version by getting the old version here and by running as root:

dpkg -i gift-turtle_1.0.0-1_i686.deb

.