diff --git a/package/sexpect/Config.in b/package/sexpect/Config.in
index bdf5c3bbf5..e558af26f0 100644
--- a/package/sexpect/Config.in
+++ b/package/sexpect/Config.in
@@ -1,5 +1,6 @@
 config BR2_PACKAGE_SEXPECT
 	bool "sexpect"
+	depends on BR2_USE_MMU # fork()
 	help
 	  sexpect is another implementation of Expect which is
 	  specifically designed for Shell scripts