You can specify either a host and a port number or you can specify an absolute url.
<target host="string" port="integer">
<ssl />?
</target>
or
<target url="url" />
<serviceProxy port="80">
<target host="http://thomas-bayer.com/axis2/services/BLZService" />
</serviceProxy>
or
<serviceProxy port="80">
<target url="http://thomas-bayer.com/axis2/services/BLZService" />
</serviceProxy>