diff --git a/ChangeLog b/ChangeLog
index d42326c2c..caa6c4383 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2006-05-14  Matthieu Herrb <matthieu.herrb@laas.fr>
+
+	* configure.ac:
+	Don't use AM_CONDITIONAL inside shell conditionals.
+	Bugzilla #6916.
+
 Fri May 12 17:51:26 2006  Søren Sandmann  <sandmann@redhat.com>
 
 	* Xext/sync.c (SyncDeleteTriggerFromCounter): Keep track of the
diff --git a/configure.ac b/configure.ac
index 542d8199a..306b41f20 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1053,11 +1053,11 @@ if test "x$XORG" = xyes -o "x$XGL" = xyes; then
 		XORG_OS_SUBDIR="linux"
 		XORG_OS_KBD="Lnx"
 		xorg_bus_linuxpci="yes"
-		AM_CONDITIONAL(LNXACPI,false)
+		linux_acpi="no"
 		case $host_cpu in
 		  ia64*)
 			linux_ia64=yes
-			AM_CONDITIONAL(LNXACPI,true)
+			linux_acpi="yes"
 			;;
 		  alpha*)
 		  	linux_alpha=yes
@@ -1065,7 +1065,7 @@ if test "x$XORG" = xyes -o "x$XGL" = xyes; then
 			xorg_bus_linuxpci="no"
 			;;
 		  x86*)
-			AM_CONDITIONAL(LNXACPI,true)
+			linux_acpi="yes"
 			;;
 		  *)
 			;;
@@ -1282,6 +1282,7 @@ AM_CONDITIONAL([XORG_BUS_SPARC], [test "x$xorg_bus_sparc" = xyes])
 AM_CONDITIONAL([XORG_LOADER_SPARC], [test "x$xorg_loader_sparcmuldiv" = xyes])
 AM_CONDITIONAL([LINUX_IA64], [test "x$linux_ia64" = xyes])
 AM_CONDITIONAL([LINUX_ALPHA], [test "x$linux_alpha" = xyes])
+AM_CONDITIONAL([LNXACPI], [test "x$linux_acpi" = xyes])
 AM_CONDITIONAL([SOLARIS_USL_CONSOLE], [test "x$solaris_usl_console" = xyes])
 AM_CONDITIONAL([SOLARIS_ASM_INLINE], [test "x$solaris_asm_inline" = xyes])
 AM_CONDITIONAL(MFB, [test "x$XORG" = xyes])