Trying to use tag-pattern inside a folder-hook

[Mason, Sam]

Hi all,

I am trying to get mutt (1.3.28i) to automatically tag all messages
older than a specific date.  I thought I would enter something like:

  folder-hook . 'tag-pattern ~d >1w'

But it just comes up with "tag-pattern: unknown command".  I'm sure
I'm doing something simple wrong, I just don't know what.

Thanks
  Sam.