Resin, Postgre driver problem

[eluser]Unknown[/eluser]
hi everyone.hope someone can help me with my prob.
im running my CI code in Resin-3.1.0 and every time i load the database class in my autoload.php im getting this exception :

com.caucho.quercus.QuercusException: no matching class CI_DB_postgre_driver

i doubt if it has something to do with my postgre driver's directory coz i can connect to my database before i recode to CI fortmat.i have my postgre driver in WEB-INF at ROOT.
pls help me.