Not sure why I cannot get this to work.
Eudora 5.2, Mac OS 8.6
--> set field "x-attachments" of message 0 to ...
<gives> "Cant make some data into the expected type"

tell application "Eudora"
        make message at end of mailbox "out" of mail folder ""
        set field "to" of message 0 to "[log in to unmask]"
        set field "subject" of message 0 to "please send information"
        set field "" of message 0 to "test for Desktop Folder:FMkrSessionNotes"
        --set theAttachments to the file "FMkrSessionNotes" of folder
desktop as alias
        tell application "Finder" to set theAttachments to
"MacHD:Desktop Folder:FMkrSessionNotes" as alias
        set field "x-attachments" of message 0 to theAttachments as alias
        queue message 0
end tell

variations tried:

        set field "x-attachments" of message 0 to theAttachments as alias
        set field "x-attachments" of message 0 to ("MacHD:Desktop
Folder:FMkrSessionNotes" as alias)
        set field "x-attachments" of message 0 to "MacHD:Desktop
Folder:FMkrSessionNotes"

also tried
set theAttachments to {}
set theAttachments to "OS8.6 10Gig:Desktop Folder:FMkrSessionNotes" as alias
tell application "Eudora"
        make message at end of mailbox "out" of mail folder ""
        set field "to" of message 0 to "[log in to unmask]"
        set field "subject" of message 0 to "please send information"
        set field "" of message 0 to "test for Desktop Folder:FMkrSessionNotes"
        set field "x-attachments" of message 0 to theAttachments
        queue message 0
end tell

Thank you for your help.
--
Jim Ault
Las Vegas
"The world is filled with willing people... Some willing to work, the
rest willing to let them."
   - - Robert Frost