diff --git a/configure.ac b/configure.ac
index c6ecba418..d27ca2392 100644
--- a/configure.ac
+++ b/configure.ac
@@ -215,7 +215,7 @@ AC_SUBST(DLOPEN_LIBS)
 dnl Checks for library functions.
 AC_CHECK_FUNCS([backtrace ffs geteuid getuid issetugid getresuid \
 	getdtablesize getifaddrs getpeereid getpeerucred getzoneid \
-	mmap shmctl64 strncasecmp vasprintf vsnprintf walkcontext])
+	mmap seteuid shmctl64 strncasecmp vasprintf vsnprintf walkcontext])
 AC_REPLACE_FUNCS([strcasecmp strcasestr strlcat strlcpy strndup])
 
 dnl Find the math libary, then check for cbrt function in it.
diff --git a/hw/xfree86/parser/write.c b/hw/xfree86/parser/write.c
index 9c706a062..26739b933 100644
--- a/hw/xfree86/parser/write.c
+++ b/hw/xfree86/parser/write.c
@@ -55,6 +55,7 @@
 #include <xorg-config.h>
 #endif
 
+#include "os.h"
 #include "xf86Parser.h"
 #include "xf86tokens.h"
 #include "Configint.h"
@@ -65,7 +66,7 @@
 #include <signal.h>
 #include <errno.h>
 
-#if defined(SVR4) || defined(__linux__) || defined(CSRG_BASED)
+#if defined(HAVE_SETEUID) && defined(_POSIX_SAVED_IDS) && _POSIX_SAVED_IDS > 0
 #define HAS_SAVED_IDS_AND_SETEUID
 #endif
 #if defined(WIN32)
diff --git a/include/xorg-config.h.in b/include/xorg-config.h.in
index a71b25d72..0df31aeb2 100644
--- a/include/xorg-config.h.in
+++ b/include/xorg-config.h.in
@@ -139,4 +139,7 @@
 /* Have X server platform bus support */
 #undef XSERVER_PLATFORM_BUS
 
+/* Define to 1 if you have the `seteuid' function. */
+#undef HAVE_SETEUID
+
 #endif /* _XORG_CONFIG_H_ */