aptitude says no install candidate for xulrunner but apt-cache search shows xulrunner = WTF?! (lenny)

[Anthony Baldwin <baldwinlinguas@gmail.com>]

I need xulrunner.

I get

apt-cache search xulrunner
conkeror - keyboard focused web browser with Emacs look and feel
conkeror-spawn-process-helper - spawn external processes in Conkeror
iceape-dev - Development files for the Iceape Internet Suite
liferea - feed aggregator for GNOME
liferea-xulrunner - transitional dummy package
totem-mozilla - Totem Mozilla plugin
xulrunner-1.9 - XUL + XPCOM application runner
xulrunner-1.9-dbg - Development files for the Gecko engine library
xulrunner-1.9-gnome-support - Support for GNOME in xulrunner applications
xulrunner-dev - Development files for the Gecko engine library


but sudo aptitude install xulrunner gives:
No candidate version found for xulrunner
No candidate version found for xulrunner
No packages will be installed, upgraded, or removed.

If I try sudo aptitude install xulrunner-1.9, I get:
$ sudo aptitude install xulrunner-1.9
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

I don't get it.
apt-cache shows the package exists, but aptitude says it doesn't...

What's to be done?

Thanks,
Tony


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