This is a copy of a post I sent to another forum that my be useful for Australian owners.

I have just checked out my GL/SF and there is a pollen filter fitted.
After only a few weeks it already had quite a bit of material built up in it. (I live in the bush)
A quick "blow job" was all that was needed to clear it.
As Panzer11 said... it filters all air coming onto the cabin.
Follow the link to get an idea on how to access it. www.hmaservice.com/webtech/iindex.asp?id=394877704#_394877704

One hint... to remove the glove box, squeeze the sides to allow it to drop fully so that you can access the bolts that retain it.(2)
Remove the glove box... remove the door side trim. (One screw and the rest is friction clipped) Then remove the 4 screws that retain the upper inner surround.
That will give you access to the filter access flap. It releases from the bottom. Pull the filter out. Note the direction arrow on the filter end to aid the correct re-fitting.
I think this is going to be needed to be done on a regular basis if you live in a dusty or country area.

I can post pictures of the job if anyones interested.

Seeya Geoff