Those who already upgraded to MiVB 9.0, could you try to switch some of your 52xx or 53xx phones to a SIP mode and test it? I tested 4 different phones and none of them worked:
Mitel 5312 (Main ver 06.05.00.18): after the phone booted up I could not access the phone's web interface and configure the SIP parameters
Mitel 5212: the phone did not boot to the SIP mode at all
Mitel 5330 (Main ver 6.03.03.13): after the phone booted up I could not access the phone's web interface and configure the SIP parameters
Mitel 5320e (Main ver 06.05.00.18): after the phone booted up I could not access the phone's web interface and configure the SIP parameters
Any ideas?