Massacre sparked by political rivalry in southern province in November stirs much fear.
The memory card problems, which resulted in the machines failing to read the names of candidates off ballot papers, were only discovered during final-phase testing on Monday, one week before the May 10 elections.
The decision to delay voting lies with the commission, and it has insisted the glitch will be fixed in time for the elections.
Olivar’s also said Arroyo “concerned” about the technical problems.
“The success of the automated election was one of her beat-the-odds promises at the beginning of her term,” he said.
Fifty million voters are scheduled to go to the polls on Monday to choose a replacement for Arroyo and thousands of lower-level officials.
Votes in previous Philippine elections were counted by hand, a process that meant results sometimes took weeks to be announced.
The government decided to introduce a computerised system in an effort to shorten the vote-tallying process to a few days and to minimise the potential for cheating.