How to make XEN 4.6 work with vncdisplay>100?

Question

Xen

There is a Xen 4.6 hypervisor. There is a desire to run more than 100 small virtual machines on it and so that each one has access via VNC. When setting vncdisplay>100 in the virtual machine config (eg vncdisplay=101 or vncdisplay=120), the virtual machine starts normally, but the port does not appear in the list (lsof -nPi | grep qemu).
Is there a way to overcome this limitation? Or will you have to switch to another virtualization system?