How do you replace the cabin air filter on a 2002 Toyota Sienna?

A previous poster asked if there even WAS a cabin air filter and was told 'no'.

I changed the cabin air filter on my Prius. It was very simple. Just open the lower glove box, squeeze the sides slightly and you can see the filter frame on the firewall. It slides out and you remove it and replace with the new pad. It is about 10" by 10".

After spending 30 minutes on the internet looking for a replacement cabin air filter for my 2001 Toyota Sienna the parts department told me the van does not have one. No wonder I have had trouble locating it! DUH