Users are growing increasingly anxious about their software contracts following the rebranding of IBM's S/390 mainframe last month.
A Computer Weekly poll of major software suppliers found considerable uncertainty about how the move to the new z900 mainframe will affect users.
Computer Associates (CA) and SAS said they would guarantee that their existing contracts for the S/390 operating system would cover the new z/OS, but were unable to confirm their stance with regard to IBM's new workload pricing policy.
"We are currently evaluating the new License Manager but to date no announcement has been made on support for workload charging," said Jay Huff, marketing director at CA.
Compuware, Software AG and Cincom were unable to say whether their pricing structures would change for users employing applications in the same way as they did on the S/390.
Workload pricing lets users pay for the software capacity they need, as opposed to the current system of total capacity pricing. Z/900 users qualify for the full benefits of workload pricing by running the z/OS and the new IBM License Manager product, which will be available late next year.
"As always, you hope that there won't be any stiffing," said Ian Rickwood, chief executive of the Institute for the Management of Information Systems. "Unfortunately, when contracts change it can open up a can of worms."
One large S/390 user said, "It all comes down to making sure that you get the right terms and conditions. The simple fact is that if a contract is ambiguous there will be scope for stiffing."
At a recent presentation to the Guide Share Europe user group at IBM's Bedfont Lakes site, Roy Hunt of IBM said the company's existing contracts would not need to be renegotiated if customers move to the z/OS on z/900 architecture processors.