It's from the old system... Something was changed back then when we had to speak to NPC's with "Hello NPC_name" and that still has to be reverted for this to work. It's something trivial, I'm sure they'll fix it soon.
I think /planeshift/src/server/questmanager.cpp simply needs to be reverted back to the old version, i.e. from version 1.97 to 1.96 in the cvs.