@@ -150,11 +150,11 @@
 	if (length == 0)
 		return;
 
 	if (calculated)
 		@throw [OFHashAlreadyCalculatedException
-		    exceptionWithClass: isa
+		    exceptionWithClass: [self class]
 				  hash: self];
 
 	/* Update bitcount */
 	t = bits[0];
 	if ((bits[0] = t + ((uint32_t)length << 3)) < t)