diff --git a/release/sysinstall/disks.c b/release/sysinstall/disks.c
index b49cf8b1a32d..493252888e03 100644
--- a/release/sysinstall/disks.c
+++ b/release/sysinstall/disks.c
@@ -362,14 +362,24 @@ diskPartition(Device *dev)
 	    break;
 
 	case 'A':
+	case 'F':	/* Undocumented magic Dangerously Dedicated mode */
 #ifdef __alpha__
 	    rv = 1;
 #else	    /* The rest is only relevant on x86 */
 	    cp = variable_get(VAR_DEDICATE_DISK);
 	    if (cp && !strcasecmp(cp, "always"))
 		rv = 1;
-	    else
+	    else if (toupper(key) == 'A')
 		rv = 0;
+	    else {
+		rv = msgYesNo("Do you want to do this with a true partition entry\n"
+			      "so as to remain cooperative with any future possible\n"
+			      "operating systems on the drive(s)?\n"
+			      "(See also the section about ``dangerously dedicated''\n"
+			      "disks in the FreeBSD FAQ.)");
+		if (rv == -1)
+		    rv = 0;
+	    }
 #endif
 	    All_FreeBSD(d, rv);
 	    variable_set2(DISK_PARTITIONED, "yes", 0);
diff --git a/usr.sbin/sade/disks.c b/usr.sbin/sade/disks.c
index b49cf8b1a32d..493252888e03 100644
--- a/usr.sbin/sade/disks.c
+++ b/usr.sbin/sade/disks.c
@@ -362,14 +362,24 @@ diskPartition(Device *dev)
 	    break;
 
 	case 'A':
+	case 'F':	/* Undocumented magic Dangerously Dedicated mode */
 #ifdef __alpha__
 	    rv = 1;
 #else	    /* The rest is only relevant on x86 */
 	    cp = variable_get(VAR_DEDICATE_DISK);
 	    if (cp && !strcasecmp(cp, "always"))
 		rv = 1;
-	    else
+	    else if (toupper(key) == 'A')
 		rv = 0;
+	    else {
+		rv = msgYesNo("Do you want to do this with a true partition entry\n"
+			      "so as to remain cooperative with any future possible\n"
+			      "operating systems on the drive(s)?\n"
+			      "(See also the section about ``dangerously dedicated''\n"
+			      "disks in the FreeBSD FAQ.)");
+		if (rv == -1)
+		    rv = 0;
+	    }
 #endif
 	    All_FreeBSD(d, rv);
 	    variable_set2(DISK_PARTITIONED, "yes", 0);
diff --git a/usr.sbin/sysinstall/disks.c b/usr.sbin/sysinstall/disks.c
index b49cf8b1a32d..493252888e03 100644
--- a/usr.sbin/sysinstall/disks.c
+++ b/usr.sbin/sysinstall/disks.c
@@ -362,14 +362,24 @@ diskPartition(Device *dev)
 	    break;
 
 	case 'A':
+	case 'F':	/* Undocumented magic Dangerously Dedicated mode */
 #ifdef __alpha__
 	    rv = 1;
 #else	    /* The rest is only relevant on x86 */
 	    cp = variable_get(VAR_DEDICATE_DISK);
 	    if (cp && !strcasecmp(cp, "always"))
 		rv = 1;
-	    else
+	    else if (toupper(key) == 'A')
 		rv = 0;
+	    else {
+		rv = msgYesNo("Do you want to do this with a true partition entry\n"
+			      "so as to remain cooperative with any future possible\n"
+			      "operating systems on the drive(s)?\n"
+			      "(See also the section about ``dangerously dedicated''\n"
+			      "disks in the FreeBSD FAQ.)");
+		if (rv == -1)
+		    rv = 0;
+	    }
 #endif
 	    All_FreeBSD(d, rv);
 	    variable_set2(DISK_PARTITIONED, "yes", 0);