diff --git a/test/rdoc/test_rdoc_servlet.rb b/test/rdoc/test_rdoc_servlet.rb
index 1127408193..977251308a 100644
--- a/test/rdoc/test_rdoc_servlet.rb
+++ b/test/rdoc/test_rdoc_servlet.rb
@@ -45,7 +45,8 @@ class TestRDocServlet < RDoc::TestCase
     @orig_base = RDoc::RI::Paths::BASE
     RDoc::RI::Paths::BASE.replace @base
     @orig_ri_path_homedir = RDoc::RI::Paths::HOMEDIR
-    RDoc::RI::Paths::HOMEDIR.replace @home_dir
+    RDoc::RI::Paths.send :remove_const, :HOMEDIR
+    RDoc::RI::Paths.const_set :HOMEDIR, @home_dir
 
     RDoc::RI::Paths.instance_variable_set \
       :@gemdirs, %w[/nonexistent/gems/example-1.0/ri]
@@ -60,7 +61,8 @@ class TestRDocServlet < RDoc::TestCase
     FileUtils.rm_rf @tempdir
 
     RDoc::RI::Paths::BASE.replace @orig_base
-    RDoc::RI::Paths::HOMEDIR.replace @orig_ri_path_homedir
+    RDoc::RI::Paths.send :remove_const, :HOMEDIR
+    RDoc::RI::Paths.const_set :HOMEDIR, @orig_ri_path_homedir
     RDoc::RI::Paths.instance_variable_set :@gemdirs, nil
   end