evolution-sharp package not available in Ubuntu (Karmic) despite reported as such

I am trying to build Tasque. http://live.gnome.org/Tasque/ When running the ./configure script, I got the following error:

...
checking for EVOLUTION_SHARP... configure: error: Package requirements (evolution-sharp >= 0.18.1) were not met:

No package 'evolution-sharp' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables EVOLUTION_SHARP_CFLAGS
and EVOLUTION_SHARP_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
...

I then tried

apt-get install evolution-sharp

However this failed

...
E: Couldn't find package evolution-sharp

So I tried looking for what package it might be in, but neither apt-cache search evolution-sharp, nor aptitude search evolution-sharp, nor the Ubuntu package search http://packages.ubuntu.com/search?suite=default&section=all&arch=any&searchon=names&keywords=evolution-sharp returned any results. Oddly enough, by doing a Google search for "ubuntu evolution-sharp" I found this project page https://launchpad.net/ubuntu/+source/evolution-sharp which reports availability of the package in Karmic, as well as numerous previous and forthcoming releases. But clearly this package is not retrievable by apt-get, so how can it be marked as available in Ubuntu?