void main()
{

object oPC = GetEnteringObject();

 if (!GetIsPC(oPC)) return;
 int DoOnce = GetLocalInt(oPC, GetTag(OBJECT_SELF));

if (DoOnce==TRUE) return;

SetLocalInt(oPC, GetTag(OBJECT_SELF), TRUE);
int iClass = GetClassByPosition(1|2|3,oPC);
if (iClass== CLASS_TYPE_DRUID || CLASS_TYPE_RANGER)
{
  SendMessageToPC(oPC, "The balance of nature as been disturbed here");
}
else
{
 SendMessageToPC(oPC, "Why are these dryads attacking, something is wrong here");
 }
}