1.8.1: dudders binary missing; RFC 2136 Dynamic DNS updates dont work

Dear all,

i was debugging dynamic dns updates on my newly updated m0n0wall.

RFC 2136 Dynamic DNS updates dont work because the dudders binary is not
present in the filesystem.

Thats my version string:
> Version 	1.8.1 built on Wed Jan 15 13:32:38 CET 2014

> $ cat /etc/inc/services.inc
[snip]
> $cmd = "/usr/local/bin/dudders";

> $ ls /usr/local/bin/
> croen
> dnswatch
> ez-ipupdate
> mbmon
> minicron
> php
> runsntp.sh
> verifysig
> voucher
> wol

Greetings,
Tobias