diff --git configure.ac configure.ac
index 5c73168a..abbf4135 100644
--- configure.ac
+++ configure.ac
@@ -138,8 +138,15 @@ AC_CHECK_FUNC(dlopen, [],
 AC_SUBST(DLOPEN_LIBS)

 # checking for openssl
-PKG_CHECK_MODULES([OPENSSL], [openssl >= 0], [],
-  [AC_MSG_ERROR([please install libssl-dev or openssl-devel])])
+if test "x$freebsd" = "xyes"; then
+  # FreeBSD base doesn't supply "*.pc"
+  AC_CHECK_HEADER([openssl/rc4.h], [],
+    [AC_MSG_ERROR([please install libssl-dev or openssl-devel])],
+    [#include <stdlib.h>])
+else
+  PKG_CHECK_MODULES([OPENSSL], [openssl >= 0], [],
+    [AC_MSG_ERROR([please install libssl-dev or openssl-devel])])
+fi

 # checking for pam variation
 # Linux-PAM is used in Linux systems