For the current 2010 Harvest festival this quest has been changed slightly. Now you need to do you tricks for the following dwarves:
Labourer in the west tunnel leading to the tavern; /whistle
Townperson watching the archery practice, west side of main hall; /mock
Townperson near the workbenches, east side of Maker's Hall; /drink
Townperson by a forge in the north-west of the Forge hall; /flex