[Draupner]

OK in OP_Castspell (clientprocess.cpp if you didn't know)

under

CastSpell_Struct* castspell = (CastSpell_Struct*)app->pBuffer;

This particular example will not let complete heal (spell id 13) to be cast in nexus (zone id 152) and will display in yellow text Can't cast spell here.

if (zone->GetZoneID() == 152 && castspell->spell_id == 13) 
					{
						Message(15, "Can't cast spell here.");
						InterruptSpell(castspell->spell_id);
						break;
					}