diff --git a/manifests/mod.pp b/manifests/mod.pp
index b6425135c9..f8f564dc9c 100644
--- a/manifests/mod.pp
+++ b/manifests/mod.pp
@@ -17,7 +17,7 @@
   $mod_lib = $mod_libs[$mod] # 2.6 compatibility hack
   if $lib {
     $lib_REAL = $lib
-  } elsif $mod_lib {
+  } elsif "${mod_lib}" {
     $lib_REAL = $mod_lib
   } else {
     $lib_REAL = "mod_${mod}.so"