diff --git a/headers/private/app/RegistrarDefs.h b/headers/private/app/RegistrarDefs.h
new file mode 100644
index 0000000000..20d9f7691f
--- /dev/null
+++ b/headers/private/app/RegistrarDefs.h
@@ -0,0 +1,57 @@
+//------------------------------------------------------------------------------
+//	Copyright (c) 2001-2002, OpenBeOS
+//
+//	Permission is hereby granted, free of charge, to any person obtaining a
+//	copy of this software and associated documentation files (the "Software"),
+//	to deal in the Software without restriction, including without limitation
+//	the rights to use, copy, modify, merge, publish, distribute, sublicense,
+//	and/or sell copies of the Software, and to permit persons to whom the
+//	Software is furnished to do so, subject to the following conditions:
+//
+//	The above copyright notice and this permission notice shall be included in
+//	all copies or substantial portions of the Software.
+//
+//	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+//	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+//	DEALINGS IN THE SOFTWARE.
+//
+//	File Name:		RegistrarDefs.h
+//	Author(s):		Ingo Weinhold (bonefish@users.sf.net)
+//	Description:	API classes - registrar interface.
+//------------------------------------------------------------------------------
+
+#ifndef REGISTRAR_DEFS_H
+#define REGISTRAR_DEFS_H
+
+#include <Errors.h>
+
+// names
+extern const char *kRegistrarSignature;
+extern const char *kRosterThreadName;
+extern const char *kRosterPortName;
+
+// message constants
+enum {
+	B_REG_SUCCESS					= 'rgsu',
+	B_REG_ERROR						= 'rger',
+	B_REG_GET_MIME_MESSENGER		= 'rgmm',
+	B_REG_GET_CLIPBOARD_MESSENGER	= 'rgcm',
+};
+
+// type constants
+enum {
+	B_REG_APP_INFO_TYPE				= 'rgai',	// app_info
+};
+
+// error constants
+#define B_REGISTRAR_ERROR_BASE		(B_ERRORS_END + 1)
+
+enum {
+	B_REG_ALREADY_REGISTERED		= B_REGISTRAR_ERROR_BASE,
+};
+
+#endif	// REGISTRAR_DEFS_H
diff --git a/src/kits/app/RegistrarDefs.cpp b/src/kits/app/RegistrarDefs.cpp
new file mode 100644
index 0000000000..a1fda3bebd
--- /dev/null
+++ b/src/kits/app/RegistrarDefs.cpp
@@ -0,0 +1,33 @@
+//------------------------------------------------------------------------------
+//	Copyright (c) 2001-2002, OpenBeOS
+//
+//	Permission is hereby granted, free of charge, to any person obtaining a
+//	copy of this software and associated documentation files (the "Software"),
+//	to deal in the Software without restriction, including without limitation
+//	the rights to use, copy, modify, merge, publish, distribute, sublicense,
+//	and/or sell copies of the Software, and to permit persons to whom the
+//	Software is furnished to do so, subject to the following conditions:
+//
+//	The above copyright notice and this permission notice shall be included in
+//	all copies or substantial portions of the Software.
+//
+//	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+//	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+//	DEALINGS IN THE SOFTWARE.
+//
+//	File Name:		RegistrarDefs.cpp
+//	Author(s):		Ingo Weinhold (bonefish@users.sf.net)
+//	Description:	API classes - registrar interface.
+//------------------------------------------------------------------------------
+
+#include <RegistrarDefs.h>
+
+// names
+const char *kRegistrarSignature	= "application/x-vnd.OBOS-Registrar";
+const char *kRosterThreadName	= "_obos_roster_thread_";
+const char *kRosterPortName		= "_obos_roster_port_";
+