The Tokyo Stock Exchange has replaced its Fujitsu trading system with a product from Hitachi to guard against future systems failings.
The move comes after capacity problems in January forced the Exchange to cut short trading on several days when the number of trades executed neared system capacity.
The Hitachi system can process five million trades a day, which is the same number as the newly upgraded Fujitsu system can handle, but an exchange spokesman said the replacement system could be more easily expanded to meet future surges in demand.
The Tokyo Stock Exchange's decision replace the Fujitsu system follows not just last month's capacity problems but also a crash in November 2005 which stopped trading in stocks and bonds for more than four hours. The crash was the most serious incident at the exchange since it switched from floor trading to an electronic trading platform in 1999.
Hitachi was brought in within a week of a new IT director taking over. Yoshinori Suzuki joined the Tokyo Stock Exchange from telecoms company NTT with a brief to revive investor confidence in the exchange's technology infrastructure. He has been given an IT budget that is twice that of his predecessor.
The Tokyo Stock Exchange is lagging behind other international exchanges in systems development. The London Stock Exchange and the New York Stock Exchange have both been building in spare trading capacity in the past year.
The London Stock Exchange has undertaken three capacity upgrades, the most recent in October last year, as part of a four-year technology programme which will culminate next year with the launch of a new trading platform.