Yes that's him! The smiley twinkling voice behind The Postie on Sounds of the City is actually NZ comedian Simon McKinney. He had a great time with The Postie character and created a fun adult with a huge touch of silliness. You can hear it when he sings on the CD "dum de do do do do doo!! "
Simon won best Male Comedian at the NZ awards a few years back. He has a tonne of talent and is a really great guy to work with. Funfact: he also voiced 'Hamish the Fish' some years back ... Find his bio here