The dialplan :

<?xml version="1.0" encoding="utf-8"?>
<!-- http://wiki.freeswitch.org/wiki/Dialplan_XML -->
<include>

<context name="mydialplan">
             <extension name="dial1">
                 <condition field="destination_number" expression="^.*$">

You forgot the parens around .*
It should be expression="^(.*)$" if you plan to use $1 later in the extension...
 

                     <!-- Dial Back -->
                        <action application="set"
data="absolute_codec_string=PCMA"/>
                     <action application="bridge"
data="sofia/gateway/sipp01/$1"/>
... like here ^^^^^^^
:)
-MC
 

                 </condition>
             </extension>
</context>

</include>