What’s new in 4.4:

*) snmp – fixed snmp version three;
*) snmp – fixed vlan interface speed;
*) hotspot – fixed radius variables in hotspot html pages;
*) removed support for xen;
*) routing – added support for BFD protocol;
*) fixed problem – MetaROUTER sometimes froze on RB4xx;
*) fixed OSPFv3 on bridge interfaces;

Download Here
http://www.dcsindo.com/support/download/firmware/