why apt-get cannot install any application?

Question

Hi ,

when trying to install application using apt-get, I always get

/bin/sh: /usr/sbin/dpkg-preconfigure: not found

for example:

$sudo apt-get install libssl-dev
[sudo] password for camino:
Reading package lists... Done
Building dependency tree
Reading state information... Done
....

Do you want to continue [Y/n]? y
WARNING: The following packages cannot be authenticated!
libssl-dev libssl0.9.8
Install these packages without verification [y/N]? y

/bin/sh: /usr/sbin/dpkg-preconfigure: not found
Setting up debconf (1.5.35+maemo3+0m6) ...
exec: 19: /usr/share/debconf/frontend: not found
dpkg: error processing debconf (--configure):
subprocess installed post-installation script returned error exit status 2
Errors were encountered while processing:
debconf

any suggestions?

Thanks.