diff --git a/divastreaming/diva_streaming_idi_host_ifc_impl.c b/divastreaming/diva_streaming_idi_host_ifc_impl.c
index 6aa3539..6cc1950 100644
--- a/divastreaming/diva_streaming_idi_host_ifc_impl.c
+++ b/divastreaming/diva_streaming_idi_host_ifc_impl.c
@@ -335,7 +335,7 @@ static int init (struct _diva_streaming_idi_host_ifc_w* ifc, dword version, dwor
 		byte* p = ifc->remote_counter_mapped_base;
 		ifc->remote_counter_mapped = (dword*)&p[ifc->remote_counter_offset];
 	} else {
-		DBG_TRC(("use system call [%s]", ifc->trace_ident))
+		DBG_TRC(("stream uses system call [%s]", ifc->trace_ident))
 	}
 
 	return (0);
diff --git a/divastreaming/segment_alloc.c b/divastreaming/segment_alloc.c
index fee8796..0c7437a 100644
--- a/divastreaming/segment_alloc.c
+++ b/divastreaming/segment_alloc.c
@@ -59,6 +59,7 @@ typedef struct _diva_segment_alloc {
 #if defined(LINUX)
 	int fd;
 	int fd_mem;
+	int fd_xdi;
 #endif
 #else
 	DESCRIPTOR* d;
@@ -133,9 +134,10 @@ int diva_create_segment_alloc  (void* os_context, struct _diva_segment_alloc** s
 #if defined(DIVA_USERMODE) /* { */
 #if defined(LINUX) /* { */
 		pI->fd = open ("/dev/DivasMAP", O_RDWR | O_NONBLOCK); /** \todo use hardware related DMA entry, needs update of XDI driver */
-    pI->fd_mem = open ("/dev/mem", O_RDWR | O_NONBLOCK);
+    pI->fd_mem = open ("/dev/mem", O_RDWR | O_NONBLOCK); /* /dev/mem is optional */
+    pI->fd_xdi = open ("/dev/DivasXDI", O_RDWR | O_NONBLOCK); /* /dev/mem is optional */
 
-		if (pI->fd >= 0 && pI->fd_mem >= 0) {
+		if (pI->fd >= 0 && (pI->fd_mem >= 0 || pI->fd_xdi >= 0)) {
 			*segment_alloc = pI;
 		} else {
 			diva_destroy_segment_alloc (&pI);
@@ -214,6 +216,8 @@ int diva_destroy_segment_alloc (struct _diva_segment_alloc** segment_alloc) {
 			close (pI->fd);
 		if (pI->fd_mem >= 0)
 			close (pI->fd_mem);
+		if (pI->fd_xdi >= 0)
+			close (pI->fd_xdi);
 #endif
 #else
 
@@ -337,10 +341,13 @@ static void* map_address (struct _diva_segment_alloc* pI, dword lo, dword hi, in
 #if defined(DIVA_USERMODE)
 #if defined(LINUX)
 	qword addr = ((qword)lo) | (((qword)hi) << 32);
+	int effective_map_fd = (map_host == 0) ? pI->fd_mem : pI->fd;
 
-	ret = mmap (0, 4*1024, PROT_READ|PROT_WRITE, MAP_SHARED, (map_host == 0) ? pI->fd_mem : pI->fd, addr);
-	if (ret == ((void*)-1)) {
-		ret = 0;
+	if (effective_map_fd >= 0) {
+		ret = mmap (0, 4*1024, PROT_READ|PROT_WRITE, MAP_SHARED, effective_map_fd, addr);
+		if (ret == ((void*)-1)) {
+			ret = 0;
+		}
 	}
 #endif
 #else
@@ -379,10 +386,23 @@ static void* umap_address (struct _diva_segment_alloc* ifc, dword lo, dword hi,
 	return (0);
 }
 
-static int write_address (struct _diva_segment_alloc* ifc, dword lo, dword hi, dword data) {
-	DBG_ERR(("%s %s at %d", __FILE__, "write_address", __LINE__))
+static int write_address (struct _diva_segment_alloc* pI, dword lo, dword hi, dword data) {
+	diva_xdi_direct_access_cmd_t cmd;
+	int ret;
 
-	return (-1);
+	if (unlikely(pI->fd_xdi < 0))
+		return (-1);
+
+
+	cmd.hdr.ident = DIVA_XDI_DIRECT_ACCESS_CMD_IDENT;
+	cmd.hdr.cmd   = DIVA_XDI_DIRECT_ACCESS_CMD_WRITE_BY_ADDRESS;
+	cmd.cmd.write_by_address.address = lo;
+	cmd.cmd.write_by_address.value   = data;
+
+	ret = write (pI->fd_xdi, &cmd, sizeof(cmd.hdr)+sizeof(cmd.cmd.write_by_address)) ==
+					sizeof(cmd.hdr)+sizeof(cmd.cmd.write_by_address) ? 0 : -1;
+
+	return (ret);
 }
 
 static void resource_removed (struct _diva_segment_alloc* pI) {
diff --git a/divastreaming/xdi_msg.h b/divastreaming/xdi_msg.h
index cf8cb21..4353e2f 100755
--- a/divastreaming/xdi_msg.h
+++ b/divastreaming/xdi_msg.h
@@ -1,11 +1,15 @@
+
 /*
  *
-  Copyright (c) Dialogic (R) 2009 - 2010
+  Copyright (c) Dialogic(R), 2010-2011
+  Copyright 2000-2003 by Armin Schindler (mac@melware.de)
+  Copyright 2000-2003 Cytronics & Melware (info@melware.de)
+
  *
   This source file is supplied for the use with
-  Eicon Networks range of DIVA Server Adapters.
+  Dialogic range of Adapters.
  *
-  Dialogic (R) File Revision :    1.9
+  Dialogic(R) File Revision :    2.1
  *
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,6 +26,7 @@
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  *
  */
+
 #ifndef __DIVA_XDI_UM_CFG_MESSSGE_H__
 #define __DIVA_XDI_UM_CFG_MESSAGE_H__
 
@@ -307,5 +312,27 @@ typedef struct _diva_xdi_io_cmd {
   void * cmd;
 } diva_xdi_io_cmd;
 
+/*
+ * Diva direct interface access commands
+ */
+#define DIVA_XDI_DIRECT_ACCESS_CMD_IDENT 0x1234abcd
+typedef struct _diva_xdi_direct_access_cmd_hdr {
+	dword ident;
+	dword cmd;
+} diva_xdi_direct_access_cmd_hdr_t;
+
+#define DIVA_XDI_DIRECT_ACCESS_CMD_WRITE_BY_ADDRESS 1
+typedef struct _diva_xdi_direct_access_write_by_address {
+	dword address;
+	dword value;
+} diva_xdi_direct_access_write_by_address_t;
+
+typedef struct _diva_xdi_direct_access_cmd {
+	diva_xdi_direct_access_cmd_hdr_t hdr;
+	union {
+		diva_xdi_direct_access_write_by_address_t write_by_address;
+	} cmd;
+} diva_xdi_direct_access_cmd_t;
+
 #endif