FreeBSD Port: postfix-2.2.8,1

[Delpy]

Sorry to bother but the latest port ends with this, even though 
mysql-client-5.0.18 is already installed:

===>   postfix-2.2.8,1 depends on shared library: pcre.0 - found
===>   postfix-2.2.8,1 depends on shared library: mysqlclient.15 - not found
===>    Verifying install for mysqlclient.15 in 
/usr/ports/databases/mysql50-cli
ent
===>  Installing for mysql-client-5.0.18
===>   mysql-client-5.0.18 depends on file: /usr/local/libdata/ldconfig - 
found
===>   Generating temporary packing list
===>  Checking if databases/mysql50-client already installed
===>   mysql-client-5.0.18 is already installed
     You may wish to ``make deinstall'' and install this port again
     by ``make reinstall'' to upgrade it properly.
     If you really wish to overwrite the old port of 
databases/mysql50-client
     without deleting it first, set the variable "FORCE_PKG_REGISTER"
     in your environment or the "make install" command line.
*** Error code 1

Stop in /usr/ports/databases/mysql50-client.
*** Error code 1

Stop in /usr/ports/mail/postfix.
*** Error code 1

Stop in /usr/ports/mail/postfix.