OpenSource protocol designed based on the original Gnutella protocol, with extensability in mind and a better searching algorithm. Supports Metadata, searching by hash and other important P2P features. Mostly abbreviated as "G2" and sometimes also named "Mike's protocol" (or "MP) and not very well accepted by most of the Gnutella dev community, due to the historical naming conflict. (The conflict started because some gnutella developers argued that the "Gnutella2" name conveys an upgrade or superiority, which is why nowadays, it is mostly referred to as G2 to avoid this old conflict.)
Gnutella2 is very close to "releasable" state in MLdonkey.
It seems that some users (I do) have problems connecting to Gnutella2 nodes while others don't. If you experience this problem, you can put G2-server_connection_timeout to 20 or 25.
You could also have to update your nodes, while the core is not running (I've heard it could be), edit the gnutella2.ini and find the "redirectors" line. Then add some addresses you can find on this page. It should look like this (with more adresses) :
redirectors = [ "http://gwebcache1.limewire.com/gwebcache/cgi-bin/perlgcache.cgi";]
the redirectors command does not apply to mldonkey. what command to input a gwebcache into mldonkey??
>> By hand in gnutella2.ini.
Since MLDonkey 2.9.0 the Gnutella2 support is officially unmaintained and
disabled in MLDonkey ./configure defaults. You can still enable it by
./configure --enable-gnutella2 but you are on your own getting it to work.
Edit src/networks/gnutella2/g2Network.ml in the source and replace old redirectors with new URLs from here title.