Duo Append Mode and VMware View

Is it possible to use append mode with VMware View?

I have everything working with default “push” mode but if I try using append mode - something like “password,123456” it seems to pass the DUO authentication process but fails the VMware authentication which says “incorrect password” and prompts me to type the ‘normal’ password which then passes. I am thus assuming that VMware is being passed the full appended password.

Has anyone got this working or is it a limitation of VMware View. Not sure if its significant but I am using 2FA on the Horizon UAG only not the actual Horizon View connection server.

BTW I have tested with NTRadPing direct to the Duo proxy server and append mode works and succeeds as expected so appears to be a VMware problem.