Apache Synapse is a simple to use, lightweight and high performance Enterprise Service Bus (ESB) from Apache.

It can deal with SOAP 1.1/1.2, REST, POX, Plain Text, Binary, Hessian, FIX and other types of messages over non-blocking http/s, JMS (1.0/1.1), File systems (s/ftp, CIFS, local, tar/zip/gz..), Mail (POP3, IMAP, SMTP), AMQP, TCP/UDP, XMPP and others. It can also deal with initiating/terminating WS-Addressing, WS-Security and WS-Reliable Messaging

Please note that the project has a much longer history than the Ohloh metrics indicate, because of an SVN move. The project started in September 2005, and has had 5 major releases.

Refer to: http://people.apache.org/~asankha/synapse/statsvn/ for true code statistics