char * OnKQMLRequestString(long taskId)
Called when the client requests the result of a performative. The default behaviour is to find the expression in the server results list, and return the expression.
This is the string version. If this returns NULL (e.g. because it is not overriden by the user), then the Agent Toolkit will call OnKQMLRequest instead. The application may find it easier to create a KQML string than a KQML expression object, in which case this function should be overriden.