Index: /trunk/src/VBox/Devices/Builtins.cpp
===================================================================
--- /trunk/src/VBox/Devices/Builtins.cpp	(revision 22875)
+++ /trunk/src/VBox/Devices/Builtins.cpp	(revision 22876)
@@ -275,5 +275,5 @@
 #endif
 
-#if defined(RT_OS_DARWIN) || defined(RT_OS_LINUX) || defined(RT_OS_SOLARIS) || defined(RT_OS_WINDOWS)
+#if defined(RT_OS_DARWIN) || defined(RT_OS_LINUX) || defined(RT_OS_SOLARIS) || defined(RT_OS_WINDOWS) || defined(RT_OS_FREEBSD)
     rc = pCallbacks->pfnRegister(pCallbacks, &g_DrvHostSerial);
     if (RT_FAILURE(rc))
Index: /trunk/src/VBox/Devices/Makefile.kmk
===================================================================
--- /trunk/src/VBox/Devices/Makefile.kmk	(revision 22875)
+++ /trunk/src/VBox/Devices/Makefile.kmk	(revision 22876)
@@ -858,5 +858,6 @@
 	Storage/DrvHostFloppy% \
 	, $(Drivers_SOURCES)) \
-	Audio/ossaudio.c
+	Audio/ossaudio.c \
+	Serial/DrvHostSerial.cpp
 Drivers_SOURCES.freebsd = \
 	Network/DrvTAP.cpp
Index: /trunk/src/VBox/Devices/Serial/DrvHostSerial.cpp
===================================================================
--- /trunk/src/VBox/Devices/Serial/DrvHostSerial.cpp	(revision 22875)
+++ /trunk/src/VBox/Devices/Serial/DrvHostSerial.cpp	(revision 22876)
@@ -38,5 +38,5 @@
 #include <iprt/alloc.h>
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 # include <errno.h>
 # ifdef RT_OS_SOLARIS
@@ -114,5 +114,5 @@
     char                        *pszDevicePath;
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
     /** the device handle */
     RTFILE                      DeviceFile;
@@ -245,5 +245,5 @@
 {
     PDRVHOSTSERIAL pThis = PDMICHAR_2_DRVHOSTSERIAL(pInterface);
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
     struct termios *termiosSetup;
     int baud_rate;
@@ -518,5 +518,5 @@
             uint64_t volatile u64Now = RTTimeNanoTS(); NOREF(u64Now);
 #endif
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 
             size_t cbWritten;
@@ -599,5 +599,5 @@
             abBuf[0] = pThis->aSendQueue[iTail];
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 
             rc = RTFileWrite(pThis->DeviceFile, abBuf, cbProcessed, NULL);
@@ -764,5 +764,5 @@
             cbRemaining = cbRead;
 
-#elif defined(RT_OS_LINUX) || defined(RT_OS_SOLARIS)
+#elif defined(RT_OS_LINUX) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 
             size_t cbRead;
@@ -924,5 +924,5 @@
 {
     PDRVHOSTSERIAL pThis = PDMINS_2_DATA(pDrvIns, PDRVHOSTSERIAL);
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
     return RTFileWrite(pThis->WakeupPipeW, "", 1, NULL);
 #elif defined(RT_OS_WINDOWS)
@@ -935,5 +935,5 @@
 }
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 /* -=-=-=-=- Monitor thread -=-=-=-=- */
 
@@ -1140,5 +1140,5 @@
     PDRVHOSTSERIAL pThis = PDMICHAR_2_DRVHOSTSERIAL(pInterface);
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
     int modemStateSet = 0;
     int modemStateClear = 0;
@@ -1189,5 +1189,5 @@
      * Init basic data members and interfaces.
      */
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
     pThis->DeviceFile  = NIL_RTFILE;
 # ifdef RT_OS_DARWIN
@@ -1270,5 +1270,5 @@
             case VERR_ACCESS_DENIED:
                 return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS,
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
                                            N_("Cannot open host device '%s' for read/write access. Check the permissions "
                                               "of that device ('/bin/ls -l %s'): Most probably you need to be member "
@@ -1288,5 +1288,5 @@
 
     /* Set to non blocking I/O */
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 
     fcntl(pThis->DeviceFile, F_SETFL, O_NONBLOCK);
@@ -1340,5 +1340,5 @@
         return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS, N_("HostSerial#%d cannot create send thread"), pDrvIns->iInstance);
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
     /* Linux & darwin needs a separate thread which monitors the status lines. */
 # ifndef RT_OS_LINUX
@@ -1383,5 +1383,5 @@
     pThis->SendSem = NIL_RTSEMEVENT;
 
-#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS)
+#if defined(RT_OS_LINUX) || defined(RT_OS_DARWIN) || defined(RT_OS_SOLARIS) || defined(RT_OS_FREEBSD)
 
     if (pThis->WakeupPipeW != NIL_RTFILE)