>From the z/OS viewpoint, I believe the short answer is NO. IPL of Z/OS on a z/ARCH box *IS* ARCHLVL 2 by definition and IBM obviously is enforcing this rule..
OTOH, It may be possible to define a "9672 type" virtual machine to allow z/OS to think it is on a 31-bit machine. I am not knowledgeable enough about z/VM to know if this is possible. Any z/VM guru's out there that can help? <Is it possible, without encountering 'negative consequences', to IPL z/OS 1.4 on a 2064-1C4 (using VM) without the z900 Bimodal or Compatibility/Exploitation Features?> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html

