diff --git a/ChangeLog b/ChangeLog
index 2b573275..fa54a2e8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2008-04-13  Tatsuhiro Tsujikawa  <tujikawa at rednoah dot com>
+
+        Fixed compile error without gnutls/libgcrypt/libgpg-error and openSSL
+        installed
+        * src/ARC4Encryptor.h
+        * src/ARC4Decryptor.h
+
 2008-04-13  Tatsuhiro Tsujikawa  <tujikawa at rednoah dot com>
 
         Renamed argument from 'errno' to 'err', since errno is confused with
diff --git a/src/ARC4Decryptor.h b/src/ARC4Decryptor.h
index 39dc25cf..9f11a302 100644
--- a/src/ARC4Decryptor.h
+++ b/src/ARC4Decryptor.h
@@ -40,6 +40,26 @@
 # include "LibgcryptARC4Decryptor.h"
 #elif HAVE_LIBSSL
 # include "LibsslARC4Decryptor.h"
-#endif // HAVE_LIBSSL
+#else
+
+// provide empty implementation to compile sources without both libgcrypt and
+// openssl installed
+namespace aria2 {
+
+class ARC4Decryptor {
+public:
+  ARC4Decryptor() {}
+
+  ~ARC4Decryptor() {}
+
+  void init(const unsigned char* key, size_t keyLength) {}
+
+  void decrypt(unsigned char* out, size_t outLength,
+	       const unsigned char* in, size_t inLength) {}
+};
+
+} // namespace aria2
+
+#endif
 
 #endif // _D_ARC4_DECRYPTOR_H_
diff --git a/src/ARC4Encryptor.h b/src/ARC4Encryptor.h
index 1335b493..1df4f61d 100644
--- a/src/ARC4Encryptor.h
+++ b/src/ARC4Encryptor.h
@@ -40,6 +40,26 @@
 # include "LibgcryptARC4Encryptor.h"
 #elif HAVE_LIBSSL
 # include "LibsslARC4Encryptor.h"
-#endif // HAVE_LIBSSL
+#else
+
+// provide empty implementation to compile sources without both libgcrypt and
+// openssl installed
+namespace aria2 {
+
+class ARC4Encryptor {
+public:
+  ARC4Encryptor() {}
+
+  ~ARC4Encryptor() {}
+
+  void init(const unsigned char* key, size_t keyLength) {}
+
+  void encrypt(unsigned char* out, size_t outLength,
+	       const unsigned char* in, size_t inLength) {}
+};
+
+} // namespace aria2
+
+#endif
 
 #endif // _D_ARC4_ENCRYPTOR_H_