msg.bypassInstantMessage on VVX 501

Phone: VVX 501

Software: UC 5.7.2.1277

VoIP Server: SIP (Asterisk)

Provisioning: Config files, HTTPS

Does the msg.bypassInstantMessage parameter work with the VVX 501 (Messages button on home screen)? 

I am trying to enable both oneTouchVoicemail and bypassInstantMessage so that the Messages button goes straight to voicemail for my users.  oneTouchVoicemail works fine, but I can't get bypassInstantMessage to work - still have to press "Message Center" before the phone dials voicemail.  I verified that it applied successfully to the phone by exporting and inspecting the config.

I'm aware that this parameter does not work for Soundpoint phones without a hardware messages button, but haven't seen any info on how it applies to the VVX line.

Config:

<msg msg.bypassInstantMessage="1">
<msg.mwi msg.mwi.1.callBackMode="contact" msg.mwi.1.callBack="1234" msg.mwi.2.callBackMode="contact" msg.mwi.2.callBack="1234">
</msg.mwi></msg>

<up up.transparentLines="1" up.oneTouchVoiceMail="1">
</up>