[44net] Encrypted links on 5.8ghz. (WPA)

I dont know what is the status of this case but I am asking here if anyone had some factual information on this. As we are using the frequency that are into the ISM band, We are also using device that are type accepted for that band. Those device are used legally with encryption by normal lambda user. If we dont modify the device power and frequency would it be legal for ham to also encrypt the signal? I understand that if we would use a higher power, different channel I would understand that we are now out of the ISM band rules. Pierre VE2PF