Index: sys/dev/acpica/acpi.c
===================================================================
RCS file: /home/ncvs/src/sys/dev/acpica/acpi.c,v
retrieving revision 1.222
diff -u -r1.222 acpi.c
--- sys/dev/acpica/acpi.c	20 Apr 2006 04:21:27 -0000	1.222
+++ sys/dev/acpica/acpi.c	2 May 2006 21:58:52 -0000
@@ -293,7 +293,11 @@
      * uses UINT8 for some values and we have no tunable_byte.
      */
     AcpiGbl_AllMethodsSerialized = acpi_serialize_methods;
-    AcpiGbl_EnableInterpreterSlack = TRUE;
+    error = resource_int_value("acpi", 0, "slack_mode", &val);
+    if (error != 0 || (error == 0 && val != 0)) {
+	printf("ACPI: Interpreter slack mode is on.\n");
+	AcpiGbl_EnableInterpreterSlack = TRUE;
+    }
 
     /* Start up the ACPI CA subsystem. */
     if (ACPI_FAILURE(error = AcpiInitializeSubsystem())) {
Index: usr.sbin/acpi/acpidb/acpidb.c
===================================================================
RCS file: /home/ncvs/src/usr.sbin/acpi/acpidb/acpidb.c,v
retrieving revision 1.5
diff -u -r1.5 acpidb.c
--- usr.sbin/acpi/acpidb/acpidb.c	1 Nov 2005 22:44:08 -0000	1.5
+++ usr.sbin/acpi/acpidb/acpidb.c	2 May 2006 22:10:39 -0000
@@ -36,6 +36,7 @@
 #include <ctype.h>
 #include <err.h>
 #include <fcntl.h>
+#include <kenv.h>
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -475,7 +476,8 @@
 int
 main(int argc, char *argv[])
 {
-	char	*progname;
+	char	*progname, val[8];
+	int	len;
 
 	progname = argv[0];
 
@@ -489,7 +491,10 @@
 	 * Match kernel options for the interpreter.  Global variable names
 	 * can be found in acglobal.h.
 	 */
-	AcpiGbl_EnableInterpreterSlack = TRUE;
+	val[7] = '\0';
+	len = kenv(KENV_GET, "hint.acpi.0.slack_mode", val, 7);
+	if (len <= 0 || (len > 0 && strtol(val, NULL, 0) != 0))
+		AcpiGbl_EnableInterpreterSlack = TRUE;
 
 	aml_simulation_regload("region.ini");
 	if (load_dsdt(argv[1]) == 0) {