problem installing i-mscp 1.2.9 after update to debian jessy

After upgrading to debian jessy now i got the following error:

./imscp-autoinstall -d

[ERROR] autoinstaller::Adapter::DebianAdapter::_updatePackagesIndex: Can't call method "set" on an undefined value at /usr/share/perl5/Debconf/FrontEnd.pm line 126, <GEN0> line 5.
Use of uninitialized value $ret in scalar chomp at /usr/share/perl5/Debconf/Client/ConfModule.pm line 132, <STDIN> line 4.
Use of uninitialized value $ret in split at /usr/share/perl5/Debconf/Client/ConfModule.pm line 133, <STDIN> line 4.
Use of uninitialized value $ret[0] in string eq at /usr/share/perl5/Debconf/Client/ConfModule.pm line 134, <STDIN> line 4.
Use of uninitialized value $ret[0] in string eq at /usr/bin/debconf-apt-progress line 173, <STDIN> line 4.

What could be the reason and how to fix it ?

Thanks

Ok i found the error is here:

debconf-apt-progress --logstderr -- apt-get -y update

after executing this line i got the errors.
What i am missing

aptitude reinstall debconf

this fixes the problem
it is debian based