As I was having a lot of trouble getting PonyProg to talk to my board, it turned out that the problem was being caused by the "Reset IC ZM33064" that equips the Olimex header ( http://www.olimex.com/dev/index.html ) This IC was holding the reset line so the parallel prog could not pull it down... Once I replaced it with a more conventional RC circuit it became wonderful.
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Olimex mega 128 - word of caution
2005-07-06 by Alex De Lara