DJabberd 0.84 and earlier does not properly detect recursion during entity expansion, which allows remote attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, a similar issue to CVE-2003-1564.
http://groups.google.com/group/djabberd/msg/e3b250f3c1877ede?dmode=source