diff --git a/configure.ac b/configure.ac
index 9a87453d..71662b85 100644
--- a/configure.ac
+++ b/configure.ac
@@ -220,7 +220,7 @@ AC_CHECK_HEADERS([sys/select.h])
 # Checks for typedefs, structures, and compiler characteristics.
 
 # Checks for library functions.
-AC_CHECK_FUNCS([strtol])
+AC_CHECK_FUNCS([strtol seteuid])
 # Used in lcFile.c (see also --enable-xlocaledir settings below)
 XLOCALEDIR_IS_SAFE="no"
 AC_CHECK_FUNC([issetugid], [XLOCALEDIR_IS_SAFE="yes"]
diff --git a/src/xlibi18n/lcFile.c b/src/xlibi18n/lcFile.c
index 4e443977..2c06fa2d 100644
--- a/src/xlibi18n/lcFile.c
+++ b/src/xlibi18n/lcFile.c
@@ -36,7 +36,7 @@
 
 /************************************************************************/
 
-#ifdef __UNIXOS2__
+#ifndef HAVE_SETEUID
 # define seteuid setuid
 #endif
 #define	iscomment(ch)	((ch) == '#' || (ch) == '\0')