HP had said it would end support for MPE by the end of 2006. It now says it is re-assessing the situation and will make an announcement in June 2004.
The Unix-based MPE (Multi-Programming Executive) operating system was used on HP's e3000 server line until the company stopped selling the servers last autumn.
But existing e3000 users have put pressure on HP to allow them to use the MPE software on the HP 9000 server, the replacement for the e3000. This would allow users to carry on using core business applications with little modification.
Analysts estimate there are 20,000 e3000 users worldwide. MPE users include American Airlines, Chase Manhattan Bank, Exxon Mobil and Ford. Large companies typically use it to power reservations systems and order processing packages.
Some users have demanded that HP make MPE open source to allow them to develop further applications. There is also a move to develop an emulator system to enable users to run MPE on the HP 9000 and other hardware.
HP has said it will not make a decision on whether to make MPE open source until the middle of 2005.
HP wrote to users earlier this month to tell them the support situation was being reconsidered, although David Wilde, HP's e3000 business manager, has told users that even if a solution was found to transfer MPE onto the HP 9000, it would not work on all platforms. "Differences in firmware and various components may make it impossible in some cases," he said.