Duser_Driver/username_exists: return null if not implemented

false means we know it doesn't exist, null means we don't know.

Signed-off-by: Florian Pritz <bluewind@xinu.at>

1 files changed, 1 insertions, 1 deletions

diff --git a/application/libraries/Duser/Duser.php b/application/libraries/Duser/Duser.php
index ecb0cd9c7..42d6b1d62 100644
--- a/application/libraries/Duser/Duser.php
+++ b/application/libraries/Duser/Duser.php
@@ -29,7 +29,7 @@ abstract class Duser_Driver extends CI_Driver {
 	abstract public function login($username, $password);
 
 	public function username_exists($username) {
-		return false;
+		return null;
 	}
 
 	public function get_email($userid) {