In Reply to: how long posted by Reculvers on Monday, 22. April 2013 at 08:19 Bali Time:
If you put it in your phone here and check the credit which with a simpati is done by pressing
*888# to check credit
and you receive a little message in Indonesian with gives you your remaining credit Rp ***** and an expiry date and they can be topped up from here if still valid.
And WSS will post how to do that when he reads this :)
Hope this helps