--- a/interp.c	Mon Sep 28 19:48:45 2009 -0400
+++ b/interp.c	Mon Sep 28 19:49:06 2009 -0400
@@ -2703,6 +2703,7 @@
 		}
 	if(room_index_ret)
 		*room_index_ret = -1;
+	printf("Error: Can't set field %s on object with blueprint %s\n", name, company[0]->company);
 	return -1;
 }
 
@@ -2788,6 +2789,8 @@
 		}
 	if(room_index_ret)
 		*room_index_ret = -1;
+	printf("Error: Can't get field %s from object with blueprint %s\n", name, company[0]->company);
+	print_stack_trace(entry->instance);
 	return -1;
 }