tags 672433 confirmed
thanks
Oooops. I did not realized it worked magically in the past:
$ apt-get source docbook-mathml -t testing
$ cat docbook-mathml-1.0.0/debian/control | grep Dep
Build-Depends: debhelper (>> 4.0.0)
Depends: ${misc:Depends}, docbook-xml (>= 4.1.2-4), w3-dtd-mathml
I'll fix this ASAP. Thanks.