Set static ip in openvpn (no more custom parameters in CSO)

[mgiammarco]

Hi,
I have an openvpn where I fixed each client ip using CSO and putting ifconfig-push in the custom field.
Now custom field is no more but I badly need this feature: I need that clients always reconnecto with same ip!
How can I do it?
This is a serious showstopper for me and no I cannot change vpn type.
Thanks,
Mario