Can AppleScript be able to click the menu extra of a 3rd-party app?
I was having an issue getting AppleScript to click on the menu extra of iTeleport Connect until I tried the following:

tell application "System Events" to tell process "iTeleport Connect"
tell (menu bar item 1 of menu bar 2)
    click --  This click appears to be the important addition that allows you to drill down to the other items
    click menu item "Connect" of menu 1
end tell
end tell