Santo Debian - Problema com depedencia.

Ola pessoal

Estou tentando isntalar a plug-in npre-2.8.1 para Nagios tem depdencia apontado para libssl-dev, e esse pacote tem a depedencia apontando para zlib1g-dev, o problema que zlib1g-dev ja instalado e tem muitos pacotes que depende dele.
Alguem sabe como resolver esse problema ???

Abaixo coloquei a saida do procedimento.

orion:/opt# aptitude install libssl-dev
Reading package lists... Done
Building dependency tree... Done
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
Building tag database... Done
The following packages are BROKEN:
libssl-dev
The following packages have been kept back:
linux-image-2.6-686 linux-image-2.6.18-4-686
0 packages upgraded, 1 newly installed, 0 to remove and 2 not upgraded.
Need to get 2086kB of archives. After unpacking 5673kB will be used.
The following packages have unmet dependencies:
libssl-dev: Depends: zlib1g-dev which is a virtual package.
Resolving dependencies...
Unable to resolve dependencies! Giving up...
Abort.