diff --git a/sbin/vinum/v.c b/sbin/vinum/v.c
index b4aac6dbf20..66f0c688c2d 100644
--- a/sbin/vinum/v.c
+++ b/sbin/vinum/v.c
@@ -134,7 +134,33 @@ main(int argc, char *argv[])
 
     superdev = open(VINUM_SUPERDEV_NAME, O_RDWR);	    /* open vinum superdevice */
     if (superdev < 0) {					    /* no go */
-	if (errno == ENOENT)				    /* we don't have our node, */
+	if (errno == ENODEV) {				    /* not configured, */
+	    superdev = open(VINUM_WRONGSUPERDEV_NAME, O_RDWR); /* do we have a debug mismatch? */
+	    if (superdev >= 0) {			    /* yup! */
+#if VINUMDEBUG
+		fprintf(stderr,
+		    "This program is compiled with debug support, but the kernel module does\n"
+		    "not have debug support.  This program must be matched with the kernel\n"
+		    "module.  Please alter /usr/src/sbin/" VINUMMOD "/Makefile and remove\n"
+		    "the option -DVINUMDEBUG from the CFLAGS definition, or alternatively\n"
+		    "edit /usr/src/sys/modules/" VINUMMOD "/Makefile and add the option\n"
+		    "-DVINUMDEBUG to the CFLAGS definition.  Then rebuild the component\n"
+		    "of your choice with 'make clean all install'.  If you rebuild the kernel\n"
+		    "module, you must stop " VINUMMOD " and restart it\n");
+#else
+		fprintf(stderr,
+		    "This program is compiled without debug support, but the kernel module\n"
+		    "includes debug support.  This program must be matched with the kernel\n"
+		    "module.  Please alter /usr/src/sbin/" VINUMMOD "/Makefile and add\n"
+		    "the option -DVINUMDEBUG to the CFLAGS definition, or alternatively\n"
+		    "edit /usr/src/sys/modules/" VINUMMOD "/Makefile and remove the option\n"
+		    "-DVINUMDEBUG from the CFLAGS definition.  Then rebuild the component\n"
+		    "of your choice with 'make clean all install'.  If you rebuild the kernel\n"
+		    "module, you must stop " VINUMMOD " and restart it\n");
+#endif
+		return 1;
+	    }
+	} else if (errno == ENOENT)			    /* we don't have our node, */
 	    make_devices();				    /* create them first */
 	if (superdev < 0) {
 	    perror("Can't open " VINUM_SUPERDEV_NAME);
@@ -402,6 +428,11 @@ make_devices(void)
 	    VINUM_SUPERDEV) < 0)
 	fprintf(stderr, "Can't create %s: %s\n", VINUM_SUPERDEV_NAME, strerror(errno));
 
+    if (mknod(VINUM_WRONGSUPERDEV_NAME,
+	    S_IRWXU | S_IFBLK,				    /* block device, user only */
+	    VINUM_WRONGSUPERDEV) < 0)
+	fprintf(stderr, "Can't create %s: %s\n", VINUM_WRONGSUPERDEV_NAME, strerror(errno));
+
     superdev = open(VINUM_SUPERDEV_NAME, O_RDWR);	    /* open the super device */
 
     if (mknod(VINUM_DAEMON_DEV_NAME,			    /* daemon super device */