How to replace the deb package with my own?

[maxl]

Hello list,

I want to replace gnupg-1.4.2.2 from synaptic with my own install of
gnupg-1.4.4

Then, if I uninstall gnupg-1.4.2.2 with synaptic, all this files are gone too:

To be removed:

gnome-app-install
libgpgme-ruby1.9
libgpgme11
libgpgme11-dev
libgpgme6
python-gnupginterface
ubuntu-keyring
ubuntu-minimal
update-manager
update-notifier

and then can't update software with synaptic as checksums can't be
verified. I tried this and messed all my system, and had to reinstall it.

Now I have both programs installed(?), and Update Manager keeps trying to
update GnuPG-1.4.4 to a lower version (1.4.2.2).

How can I replace the deb package with my own and still keeping Update
Manager functionality?

Thanks in advance.