@@ -14,10 +14,11 @@
  * file.
  */
 
 #include "config.h"
 
+#include <stdlib.h>
 #include <string.h>
 
 #import "OFSHA224Or256Hash.h"
 
 #import "OFHashAlreadyCalculatedException.h"
@@ -118,20 +119,30 @@
 + (size_t)blockSize
 {
 	return 64;
 }
 
-+ (instancetype)hash
++ (instancetype)cryptoHash
 {
 	return [[[self alloc] init] autorelease];
 }
 
 - init
 {
 	self = [super init];
 
-	[self OF_resetState];
+	@try {
+		if ([self class] == [OFSHA224Or256Hash class]) {
+			[self doesNotRecognizeSelector: _cmd];
+			abort();
+		}
+
+		[self OF_resetState];
+	} @catch (id e) {
+		[self release];
+		@throw e;
+	}
 
 	return self;
 }
 
 - (void)updateWithBuffer: (const void*)buffer_
@@ -139,11 +150,11 @@
 {
 	const uint8_t *buffer = buffer_;
 
 	if (_calculated)
 		@throw [OFHashAlreadyCalculatedException
-		    exceptionWithHash: self];
+		    exceptionWithObject: self];
 
 	_bits += (length * 8);
 
 	while (length > 0) {
 		size_t min = 64 - _bufferLength;