SITE commands are not internal commands - they are client commands.
You cannot use SITE commands directly from the scheduler, but you accomplish the same thing by executing a batch file using the "!change" command.
scripts\credits.bat
Code:
@ECHO OFF
ECHO !change neoxed credits +1024
system\ioFTPD.ini
Code:
[Scheduler]
GiveCredits = 0 23 * * EXEC ..\scripts\credits.bat