Owncloud server on ubuntu + postgresql fail to install

9.1.x
help

#1

Ubuntu 14.04 - Postgresql 9.3 - Apache2 - PHP5+pgsql.so

Install wizard error :
error trying to create admin user : failed to connect to the database : an exception occured in driver : could not find driver

0 - dummy db owncloud exist on pgsql server
1 - phpinfo() say pgsql enabled
2 - another site is working with the same services

Ideas to solve the problem ?

Merci


#2

Make sure that pdo.so as well as pdo_pgsql.so is loaded.