[root@anja:~]# aptitude install odbcinst1debian1
Reading Package Lists... Done
Building Dependency Tree       
Reading extended state information      
Initializing package states... Done
Reading task descriptions... Done  
The following packages are unused and will be REMOVED:
  libct1 libphp-adodb libpq3 php4-odbc php4-pgsql php4-snmp php4-sybase 
  rrdtool snmp unixodbc 
The following NEW packages will be automatically installed:
  ca-certificates libct3 libdb4.4 libpq4 libreadline5 libsnmp9 libssl0.9.8 
  libsysfs2 readline-common 
The following packages will be automatically REMOVED:
  cacti libapache2-mod-php4 odbcinst1 php4-mysql phpmyadmin 
[cut]


If I do an aptitude dist-upgrade:

[root@anja:~]# aptitude dist-upgrade
Reading Package Lists... Done
Building Dependency Tree       
Reading extended state information      
Initializing package states... Done
Reading task descriptions... Done  
E: Unable to correct problems, you have held broken packages.
E: Unable to correct dependencies, some packages cannot be installed
[root@anja:~]#