ZFD7 PXE/Kernel running on ZFD4.x server (NW5.1)

Is there any way I can run the ZFD7 PXE/Imaging kernel/version on my
ZFD4.X (NW5.1) servers? We have 40 servers upgraded to NW6.5 and ZFD7,
and 40 still running NW5.1 and ZFD4.01.

In order to keep things simple, we'd like to get the same kernel and
support files across all systems. Easier to have (linux, root, and
initd) on all systems and do away with Linux.1, Linux.2, and Linux.tgz.
This way we only need to update one kernel instead of two when new
drivers come out.

We we're able to do this when we went from ZFD3 to ZFD4. We just copied
the PXE files to the ZFD3 servers and ran with it.

Any help or ideas are appreciated.


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rroncme