RHEL 4.0 has lvm2. There is an executable file /sbin/lvm.static, and this is to explain what it does.
o The full set of LVM2 commands is now installed in /usr/sbin/. In boot
environments where /usr/ is not available, it is necessary to prefix
each command with /sbin/lvm.static (/sbin/lvm.static vgchange -ay, for
example).
In environments where /usr/ is available, it is no longer necessary to
prefix each command with lvm (/usr/sbin/lvm vgchange -ay becomes
/usr/sbin/vgchange -ay, for example).
o The new LVM2 commands (such as /usr/sbin/vgchange -ay and
/sbin/lvm.static vgchange -ay) detect if you are running a 2.4 kernel,
and transparently invoke the old LVM1 commands if appropriate. The
LVM1 commands have been renamed to end with ".lvm1" (for example,
/sbin/vgchange.lvm1 -ay).
See this link for more information.