What do I need for Windows 2008 R2 & SQL 2008 R2 to use 256GB of RAM

We are in the Process of upgrading our JDE SQL Server and need it to be Windows 2008 R2 and SQL 2008 R2. Our JDE Support team would like us to put 256GB of RAM on the server. Which means we need to use the Enterprise version of software.

My Question is, do we need the Enterprise version of Both Windows 2008 R2 and SQL 2008 R2?

From what I read on Microsoft website. That is what we need to do. I just need clarification on this because our JDE Support is saying we just need one of them to be Enterpise and the other Standard version. If that is true then that would be much cheaper.

Windows Server 2008 R2 Memory Limits:

http://msdn.microsoft.com/en-us/library/windows/desktop/aa366778(v=vs.85).aspx#physical_memory_limits_windows_server_2008_r2

SQL 2008 R2 Memory Limits:

http://technet.microsoft.com/en-us/library/ms143685(d=printer,v=sql.105).aspx