Applescript for mail rule

Question

I found this on Mactech. All I did was add the line "make new outgoing........", well, it does NOT work. What do you have to do to make Mail trigger an applescript. All I want to do is when I an email reminder, to just make a new email message with Happy Birthday in the Subject. I'll click the stationary and add a birthday background. Any help would be appreciated.
using terms from application "Mail"
on perform mail action with messages theSelectedMessages for rule theRule
repeat with a from 1 to count theSelectedMessages
make new outgoing message with properties {visible:true, subject:"Happy Birthday", content:"Happy Birthday "}
end repeat
end perform mail action with messages
end using terms from

Answer 1

sorry but your suggestion did NOT work. Here is what I wrote and it did NOT make a difference the script will NOT generate an outgoing message.
using terms from application "Mail"
on perform mail action with messages newMessages
repeat with newMessage in newMessages
tell application "Mail"
set senderName to (extract name from sender of newMessage)
say "You've just received an email from " & senderName
say (subject of newMessage) as string
if (subject of newMessage) contains "birthday" then
tell application "Mail"
activate
make new outgoing message with properties {visible:true, subject:"Happy Birthday", content:"Happy Birthday "}
end tell
end if
end tell
end repeat
What I was able to do was embed a line of code to call another script that does successfully create an out going message. Here is the successful script.
using terms from application "Mail"
on perform mail action with messages newMessages
repeat with newMessage in newMessages
tell application "Mail"
set senderName to (extract name from sender of newMessage)
say "You've just received an email from " & senderName
say (subject of newMessage) as string
end tell
end repeat
tell application "Finder"
open "Macintosh HD:Users:Shawn:Documents:Applescripts:Mail scripts:make outgoing email happy birthday5.app"
end tell
end perform mail action with messages
end using terms from
here is the make birthday5 app
tell application "Mail"
activate
make new outgoing message with properties {visible:true, subject:"Happy Birthday", content:"Happy Birthday "}
end tell
Now when I get my birthday reminder, according to the "Rule" set up in preferences, if the subject contains "birthday" the script will read the name and subject and generate an outgoing message with Happy Birthday in the Subject and Body.....all I have to do is add some birthday stationary, type in a sappy line and viola, done. See why I love Macs so much.