You should be able to apt-cache search pulse jack.
Its the jack backend for pulse. Sorry. (Coffee has not kicked in yet:) ) I am not at my computer but I got this information from the officual ubuntu wikis. You can google "ubuntu pulseaudio jack".
This website describes the process here. Scroll down to the pulse audio section:
https://help.ubuntu.com/community/UbuntuStudioPreparation
Jeremiah