On Wed, Mar 2, 2011 at 7:58 AM, Johan Helsingius <julf@julf.com> wrote:
Brian,

> Show us the whole dialplan.

Here is the voicemail part:

 <!-- voicemail main extension -->
   <extension name="vmain">
     <condition field="destination_number" expression="^vmain$|^\*98$">
       <action application="answer"/>
       <action application="sleep" data="1000"/>
       <action application="set" data="voicemail_authorized=${sip_authorized}"/>

Don't you need to execute this one inline? 
       <action application="set" data="voicemail_authorized=true"/>
Should be
 <action application="set" data="voicemail_authorized=true" inline="true"/>

Try that and let us know what happens.
-MC