newbie Get Content question

I am trying to get the content of a selected message in OE. I log the following output/errorr:
tell application “Outlook Express”
get current messages
get |content| of incoming message id 9473
→ Outlook Express got an error: Can’t get |content| of incoming message id 9473.
this is my script, I cant seem to "get " most properties. I dont understand. Any help?
this script adds a sig to outgoing messages *)
– figure out what messages to process
on run
set oldBody to “”
set newBody to “”
set sigText to “----------------------” & ¬
“blahblah” & ¬
tell application “Outlook Express”
set theMessages to the current messages
end tell
repeat with theMsg in theMessages
my ProcessMsg(theMsg)
end repeat end run
– process the messages on ProcessMsg(theMsg)
get content of theMsg
set oldBody to the content of theMsg
set newBody to oldBody & sigText
set content of theMsg to newBody end ProcessMsg