diff --git a/drivers/pty/tty.c b/drivers/pty/tty.c
index 32094602f..ed4f31c9d 100644
--- a/drivers/pty/tty.c
+++ b/drivers/pty/tty.c
@@ -100,7 +100,7 @@ int main(void)
 
   message tty_mess;		/* buffer for all incoming messages */
   int ipc_status;
-  unsigned line;
+  int line;
   int r;
   register tty_t *tp;
 
@@ -140,7 +140,9 @@ int main(void)
 	/* Only device requests should get to this point.
 	 * All requests have a minor device number.
 	 */
-	line = tty_mess.CDEV_MINOR;
+	if (OK != chardriver_get_minor(&tty_mess, &line))
+		continue;
+
 	if (line - PTYPX_MINOR < NR_PTYS &&
 			tty_mess.m_type != CDEV_IOCTL) {
 		/* Terminals and pseudo terminals belong together. We can only
diff --git a/drivers/tty/tty.c b/drivers/tty/tty.c
index 5470f6d72..51519cc46 100644
--- a/drivers/tty/tty.c
+++ b/drivers/tty/tty.c
@@ -149,7 +149,7 @@ int main(void)
 
   message tty_mess;		/* buffer for all incoming messages */
   int ipc_status;
-  unsigned line;
+  int line;
   int r;
   register tty_t *tp;
 
@@ -222,7 +222,9 @@ int main(void)
 	/* Only device requests should get to this point.
 	 * All requests have a minor device number.
 	 */
-	line = tty_mess.CDEV_MINOR;
+	if (OK != chardriver_get_minor(&tty_mess, &line))
+		continue;
+
 	if (line == VIDEO_MINOR) {
 		do_video(&tty_mess, ipc_status);
 		continue;
diff --git a/include/minix/chardriver.h b/include/minix/chardriver.h
index 880ab824b..48f67ae84 100644
--- a/include/minix/chardriver.h
+++ b/include/minix/chardriver.h
@@ -24,6 +24,7 @@ struct chardriver {
 
 /* Functions defined by libchardriver. */
 void chardriver_announce(void);
+int chardriver_get_minor(message *m, devminor_t *minor);
 void chardriver_process(struct chardriver *cdp, message *m_ptr,
 	int ipc_status);
 void chardriver_terminate(void);
diff --git a/include/minix/com.h b/include/minix/com.h
index 24e5c9d1b..210975317 100644
--- a/include/minix/com.h
+++ b/include/minix/com.h
@@ -1011,7 +1011,6 @@
 
 /* Field names for block device messages. */
 #define CDEV_MINOR	m10_i1	/* minor device number */
-#define CDEV_ACCESS	m10_i2	/* access bits for open requests */
 #define CDEV_GRANT	m10_i2	/* grant ID of buffer */
 #define CDEV_OPS	m10_i2	/* requested select operations */
 #define CDEV_COUNT	m10_i3	/* number of bytes to transfer */
diff --git a/include/minix/ipc.h b/include/minix/ipc.h
index 029194ecb..ed12ca229 100644
--- a/include/minix/ipc.h
+++ b/include/minix/ipc.h
@@ -1574,6 +1574,16 @@ typedef struct {
 } mess_vfs_fs_utime;
 _ASSERT_MSG_SIZE(mess_vfs_fs_utime);
 
+typedef struct {
+	endpoint_t id;
+	endpoint_t user;
+	devminor_t minor;
+	int access;
+
+	uint8_t padding[40];
+} mess_vfs_lchardriver_openclose;
+_ASSERT_MSG_SIZE(mess_vfs_lchardriver_openclose);
+
 typedef struct {
 	int status;
 	uint32_t id;		/* should be cdev_id_t */
@@ -1861,6 +1871,8 @@ typedef struct {
 
 		mess_vfs_lc_lseek	m_vfs_lc_lseek;
 
+		mess_vfs_lchardriver_openclose	m_vfs_lchardriver_openclose;
+
 		mess_vfs_utimens	m_vfs_utimens;
 		mess_vm_vfs_mmap	m_vm_vfs_mmap;
 		mess_vmmcp		m_vmmcp;
diff --git a/lib/libblockdriver/driver.c b/lib/libblockdriver/driver.c
index 42bca46aa..55e716f49 100644
--- a/lib/libblockdriver/driver.c
+++ b/lib/libblockdriver/driver.c
@@ -370,7 +370,7 @@ static void do_char_open(message *m_ptr, int ipc_status)
 
   m_reply.m_type = CDEV_REPLY;
   m_reply.m_lchardriver_vfs_reply.status = ENXIO;
-  m_reply.m_lchardriver_vfs_reply.id = m_ptr->CDEV_ID;
+  m_reply.m_lchardriver_vfs_reply.id = m_ptr->m_vfs_lchardriver_openclose.id;
 
   send_reply(m_ptr->m_source, &m_reply, ipc_status);
 }
diff --git a/lib/libchardriver/chardriver.c b/lib/libchardriver/chardriver.c
index 6b9361c3d..ab7f604f0 100644
--- a/lib/libchardriver/chardriver.c
+++ b/lib/libchardriver/chardriver.c
@@ -43,6 +43,8 @@
  *   Apr 02, 1992   constructed from AT wini and floppy driver  (Kees J. Bot)
  */
 
+#include <assert.h>
+
 #include <minix/drivers.h>
 #include <minix/chardriver.h>
 #include <minix/ds.h>
@@ -235,6 +237,12 @@ static void chardriver_reply(message *mess, int ipc_status, int r)
   switch (mess->m_type) {
   case CDEV_OPEN:
   case CDEV_CLOSE:
+	reply_mess.m_type = CDEV_REPLY;
+	reply_mess.m_lchardriver_vfs_reply.status = r;
+	reply_mess.m_lchardriver_vfs_reply.id =
+		mess->m_vfs_lchardriver_openclose.id;
+	break;
+
   case CDEV_READ:
   case CDEV_WRITE:
   case CDEV_IOCTL:
@@ -272,9 +280,9 @@ static int do_open(struct chardriver *cdp, message *m_ptr)
 	return OK;
 
   /* Call the open hook. */
-  minor = m_ptr->CDEV_MINOR;
-  access = m_ptr->CDEV_ACCESS;
-  user_endpt = m_ptr->CDEV_USER;
+  minor = m_ptr->m_vfs_lchardriver_openclose.minor;
+  access = m_ptr->m_vfs_lchardriver_openclose.access;
+  user_endpt = m_ptr->m_vfs_lchardriver_openclose.user;
 
   r = cdp->cdr_open(minor, access, user_endpt);
 
@@ -301,7 +309,7 @@ static int do_close(struct chardriver *cdp, message *m_ptr)
 	return OK;
 
   /* Call the close hook. */
-  minor = m_ptr->CDEV_MINOR;
+  minor = m_ptr->m_vfs_lchardriver_openclose.minor;
 
   return cdp->cdr_close(minor);
 }
@@ -473,16 +481,26 @@ void chardriver_process(struct chardriver *cdp, message *m_ptr, int ipc_status)
 	return;
   }
 
-  /* We might get spurious requests if the driver has been restarted. Deny any
-   * requests on devices that have not previously been opened.
-   */
-  if (IS_CDEV_RQ(m_ptr->m_type) && !is_open_dev(m_ptr->CDEV_MINOR)) {
-	/* Ignore spurious requests for unopened devices. */
-	if (m_ptr->m_type != CDEV_OPEN)
-		return; /* do not send a reply */
+  if (IS_CDEV_RQ(m_ptr->m_type)) {
+	int minor;
 
-	/* Mark the device as opened otherwise. */
-	set_open_dev(m_ptr->CDEV_MINOR);
+	/* Try to retrieve minor device number */
+	r = chardriver_get_minor(m_ptr, &minor);
+
+	if (OK != r)
+		return;
+
+	/* We might get spurious requests if the driver has been restarted.
+	 * Deny any requests on devices that have not previously been opened.
+	 */
+	if (!is_open_dev(minor)) {
+		/* Ignore spurious requests for unopened devices. */
+		if (m_ptr->m_type != CDEV_OPEN)
+			return; /* do not send a reply */
+
+		/* Mark the device as opened otherwise. */
+		set_open_dev(minor);
+	}
   }
 
   /* Call the appropriate function(s) for this request. */
@@ -540,3 +558,29 @@ void chardriver_task(struct chardriver *cdp)
 	chardriver_process(cdp, &mess, ipc_status);
   }
 }
+
+/*===========================================================================*
+ *				chardriver_get_minor			     *
+ *===========================================================================*/
+int chardriver_get_minor(message *m, devminor_t *minor)
+{
+  assert(NULL != m);
+  assert(NULL != minor);
+
+  switch(m->m_type)
+  {
+	case CDEV_OPEN:
+	case CDEV_CLOSE:
+	    *minor = m->m_vfs_lchardriver_openclose.minor;
+	    return OK;
+	case CDEV_READ:
+	case CDEV_WRITE:
+	case CDEV_IOCTL:
+	case CDEV_CANCEL:
+	case CDEV_SELECT:
+	    *minor = m->CDEV_MINOR;
+	    return OK;
+	default:
+	    return EINVAL;
+  }
+}
diff --git a/servers/vfs/device.c b/servers/vfs/device.c
index 99118d48e..3803eab5f 100644
--- a/servers/vfs/device.c
+++ b/servers/vfs/device.c
@@ -403,14 +403,17 @@ static int cdev_opcl(
   memset(&dev_mess, 0, sizeof(dev_mess));
 
   dev_mess.m_type = op;
-  dev_mess.CDEV_MINOR = minor_dev;
-  dev_mess.CDEV_ID = who_e;
+  dev_mess.m_vfs_lchardriver_openclose.minor = minor_dev;
+  dev_mess.m_vfs_lchardriver_openclose.id = who_e;
   if (op == CDEV_OPEN) {
-	dev_mess.CDEV_USER = who_e;
-	dev_mess.CDEV_ACCESS = 0;
-	if (flags & R_BIT)	dev_mess.CDEV_ACCESS |= CDEV_R_BIT;
-	if (flags & W_BIT)	dev_mess.CDEV_ACCESS |= CDEV_W_BIT;
-	if (flags & O_NOCTTY)	dev_mess.CDEV_ACCESS |= CDEV_NOCTTY;
+	dev_mess.m_vfs_lchardriver_openclose.user = who_e;
+	dev_mess.m_vfs_lchardriver_openclose.access = 0;
+	if (flags & R_BIT)
+		dev_mess.m_vfs_lchardriver_openclose.access |= CDEV_R_BIT;
+	if (flags & W_BIT)
+		dev_mess.m_vfs_lchardriver_openclose.access |= CDEV_W_BIT;
+	if (flags & O_NOCTTY)
+		dev_mess.m_vfs_lchardriver_openclose.access |= CDEV_NOCTTY;
   }
 
   /* Send the request to the driver. */