Calling a procedure from drupal
I don't know the problem, but after adding the  following piece of code in my database.ini of oracle directory and changing my calling method prepare('-----') to oraclePrepare('-------') I am able to access the stored procedure with parameters. I got the reference from here

Check for the oraclePrepare('-------') method in database.ini. If it is not there then add following lines in the DatabaseConnection_oracle class.

code Added in DatabaseConnection_oracle class of oracle's database.ini:

 public function oraclePrepare($query)
 {
     return parent::prepare($query);
  }