diff --git a/cmake/modules/UnixAuth.cmake b/cmake/modules/UnixAuth.cmake
index 904f0cb..0347251 100644
--- a/cmake/modules/UnixAuth.cmake
+++ b/cmake/modules/UnixAuth.cmake
@@ -1,4 +1,4 @@
-find_package(PAM)
+macro_optional_find_package(PAM)
 
 include(CheckFunctionExists)
 include(CheckLibraryExists)