Yes, but some time back the inbuilt stopped working because NZ is different to the rest of the world, but it does have a plugin that reads in an xml file. So for the last about 8 years I have been using the geekzone EPG Collector. I say geekzone as that is what the directory is called that it installs in. It worked perfectly till last Friday. I have only had to upgrade the collector about 2 years ago when there was a change. So every morning at 9:00am the bat file would go and update the xml. What is confusing is that my Sony TV has never had an issue till now either.
It's good to see you've got it sorted, but for clarification NZ isn't different to the rest of the world.
For the first 6 or so years of Freeview|HD it only broadcast the 8 day EPG in MHEG5 and only now and next was broadcast using the EIT EPG (the "standard" EPG) so you had to rely great apps such as EPG collector to extract the data from the MHEG5 EPG and write it to a XML file.
However the full 8 day EPG has been broadcast using EIT for probably 3 years so now so applications like NextPVR that I use I get the full 8 day EPG without needing to use any 3rd party applications. I'm just surprised that Media Portal doesn't support that yet, because the only thing that's semi unique in NZ is the use of Huffman coding on the EIT table, but that's something quite a few countries now use.