In OmniGraffle 3.2.4 the following script gets NSInternalScriptError when it gets to "make new label..."

Can anyone give me a clue?


tell application "OmniGraffle"
tell front window
tell page 1
set theLine to make new line at beginning of graphics with properties {head type:"FilledArrow", point list:{{0.0, 0.0}, {100.0, 100.0}}}
tell theLine
make new label with properties {text:"My Label"}
end tell
end tell
end tell
end tell

Richard