Opening a non-native tiff file into Photoshop...

Hi all,

How can I get a script to open a tiff, into Photoshop, that is not native to Photoshop? For instance, if I have a tiff that was created by exporting it from Freehand, it won’t open without the message “Could not find the application program that created the document …yadda yadda… To open the document, select and alternate program… yadda yadda”

Once the file is open, I have the script run an action. It works perfectly on files that are from Photoshop. Here’s a stripped down version of what I have:

tell application "finder"
  open file "freehand_file.tif" of folder "That_folder" -- How can I get "freehand_file.tif" to automatically open in Photoshop?
  tell application "Adobe Photoshop 7.0"
   do action "My Action" from "My Action Set.atn"
  end tell
end tell

Other info:
MacOS 9.2.2
Applescript 1.8.3
Photoshop 7.0.1

I’m sure the solution is simple :?

tell app "Finder" to open alias "hd:folder:whatever.tif" using application file id "8BIM" -- PS's signature