diff --git a/lib/aruba/platforms/unix_environment_variables.rb b/lib/aruba/platforms/unix_environment_variables.rb
index <HASH>..<HASH> 100644
--- a/lib/aruba/platforms/unix_environment_variables.rb
+++ b/lib/aruba/platforms/unix_environment_variables.rb
@@ -10,8 +10,8 @@ module Aruba
 
       public
 
-      def initialize
-        @env = ENV.to_hash.dup
+      def initialize(env = ENV.to_hash)
+        @env = Marshal.load(Marshal.dump(env))
       end
 
       # Update environment with other en
Real copy of unix environment as well