support unicode on MSSQL in quote

src/Sqlsrv/SqlsrvDriver.php

@@ -250,6 +250,27 @@ public function escape($text, $extra = false)
 		return $result;
 	}
 
+	/**
+	 * Quotes and optionally escapes a string to database requirements for use in database queries.
+	 *
+	 * @param   mixed    $text    A string or an array of strings to quote.
+	 * @param   boolean  $escape  True (default) to escape the string, false to leave it unchanged.
+	 *
+	 * @return  string  The quoted input string.
+	 *
+	 * @since   __DEPLOY_VERSION__
+	 */
+	public function quote($text, $escape = true)
+	{
+		if (is_array($text))
+		{
+			return parent::quote($text, $escape);
+		}
+
+		// To support unicode on MSSQL we have to add prefix N
+		return 'N\'' . ($escape ? $this->escape($text) : $text) . '\'';
+	}
+
 	/**
 	 * Determines if the connection to the server is active.
 	 *