Tigase has Roster versioning support too
Roster versioning support seems to become the fad in July since Prosody team claimed that "Prosody is currently the only server to support roster versioning".
According to the abstract of XEP-0237: Roster Versioning, this specification defines a proposed modification to the XMPP roster protocol that enables versioning of rosters such that the server will not send the roster to the client if the roster has not been modified, thus saving bandwidth during session establishment.
Exact-Match Conformance is implemented in tigase for simplicity. The entire roster will be transmitted if there is any modification of the roster.
The feature is in the trunk code on svn already and will be included in the coming release.