diff --git a/configure.ac b/configure.ac
index efb5ea1..c54692e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,6 +16,12 @@ AC_PROG_INSTALL
 
 # Checks for header files.
 AC_CHECK_HEADERS([fcntl.h stdint.h stdlib.h string.h unistd.h])
+AC_CHECK_HEADERS([sys/capability.h],
+		[],
+		[AC_MSG_ERROR([missing libcap header])])
+AC_CHECK_HEADERS([security/pam_appl.h security/pam_misc.h],
+		[],
+		[AC_MSG_ERROR([missing PAM headers])])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_UID_T