That thread says to play with these options, though it does not say how they should be set. It would have been great if the op had reported back on what worked, and what didn't. For me, nothing worked.
260 Allow NP PWG View user to have Caller ID lookup
261 Allow NP PWG View WEB access to messages.
262 Store Caller Line Id as a phone number
263 Store Caller Line Id as a phone or mailbox number
264 Play outside caller user interface (with FCOS bit 280)
280 Enable CLI Outside caller interface (with FCOS bit 264)
I couldn't get any combination of these to do what I wanted. I found the way it was set up when I started playing with it, 260 and 261 weren't checked, the rest were. I checked these two, no difference. I unchecked 263 and 264, and no new mail would show up in visual voice mail at all, though there clearly were new messages because the lamp was lit. I checked 263 and tried again, still no new messages in visual VM. I checked 264, and all four messages showed up.