diff --git a/test/test_utils.rb b/test/test_utils.rb
index e23d7d24..506fe4be 100644
--- a/test/test_utils.rb
+++ b/test/test_utils.rb
@@ -435,6 +435,8 @@ def assert_sub_process_returns(expected_lines, code, load_path = [], required =
         # https://github.com/tzinfo/tzinfo/runs/1664655982#step:8:1893
         #
         # Ignore untaint deprecation warnings from Bundler 1 on Ruby 3.0.
+        #
+        # Ignore method redefined warnings from concurrent-ruby on JRuby 9.4.
         actual_lines = actual_lines.reject do |l|
           l.start_with?('Gem::Specification#rubyforge_project= called from') ||
             l.start_with?('NOTE: Gem::Specification#rubyforge_project= is deprecated with no replacement.') ||
@@ -446,7 +448,8 @@ def assert_sub_process_returns(expected_lines, code, load_path = [], required =
             l.start_with?('WARNING: All illegal access operations will be denied in a future release') ||
             l.start_with?('WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations') ||
             l.start_with?('io/console on JRuby shells out to stty for most operations') ||
-            l =~ /\/bundler-1\..*\/lib\/bundler\/.*\.rb:\d+: warning: (Object|Pathname)#untaint is deprecated and will be removed in Ruby 3\.2\.\z/
+            l =~ /\/bundler-1\..*\/lib\/bundler\/.*\.rb:\d+: warning: (Object|Pathname)#untaint is deprecated and will be removed in Ruby 3\.2\.\z/# ||
+            l =~ /\/lib\/concurrent-ruby\/concurrent\/executor\/java_thread_pool_executor\.rb:\d+: warning: method redefined; discarding old to_(f|int)\z/
         end
 
         if RUBY_ENGINE == 'jruby' && ENV['_JAVA_OPTIONS'] && actual_lines.first == "Picked up _JAVA_OPTIONS: #{ENV['_JAVA_OPTIONS']}"