Index: bp-members/bp-members-signup.php
===================================================================
--- bp-members/bp-members-signup.php	(revision 4118)
+++ bp-members/bp-members-signup.php	(working copy)
@@ -236,7 +236,7 @@
 	if ( is_array( $value ) )
 		$db_illegal_names = $value;
 	elseif ( is_string( $value ) )
-		$db_illegal_names = implode( ' ', $names );
+		$db_illegal_names = explode( ' ', $value );
 
 	// Add the core components' slugs to the banned list even if their components aren't active.
 	$bp_component_slugs = array(