diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index ed829b645..5bb34230d 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -13,8 +13,7 @@ jobs:
           - '3.2'
           - '3.3'
           # - jruby
-          # NOTE: temporarily disable truffleruby due to weird rspec issue
-          # - truffleruby
+          - truffleruby
     name: Ruby ${{ matrix.ruby }}
     steps:
       - uses: actions/checkout@v4
diff --git a/spec/cli/commands/dns_proxy_spec.rb b/spec/cli/commands/dns_proxy_spec.rb
index b40e8959c..76458c3aa 100644
--- a/spec/cli/commands/dns_proxy_spec.rb
+++ b/spec/cli/commands/dns_proxy_spec.rb
@@ -124,16 +124,9 @@
         let(:name) { '/[abc/' }
 
         it "must raise an OptionParser::InvalidArgument" do
-          # XXX: TruffleRuby's RegexpError exception message is different
-          if RUBY_ENGINE == 'truffleruby'
-            expect {
-              subject.parse_record_name(name)
-            }.to raise_error(OptionParser::InvalidArgument,"invalid argument: invalid Regexp: premature end of char-class (org.joni.exception.SyntaxException): /[abc/")
-          else
-            expect {
-              subject.parse_record_name(name)
-            }.to raise_error(OptionParser::InvalidArgument,"invalid argument: invalid Regexp: premature end of char-class: /[abc/")
-          end
+          expect {
+            subject.parse_record_name(name)
+          }.to raise_error(OptionParser::InvalidArgument,"invalid argument: invalid Regexp: premature end of char-class: /[abc/")
         end
       end
     end
@@ -196,16 +189,9 @@
         let(:name) { '/[abc/' }
 
         it "must raise an OptionParser::InvalidArgument" do
-          # XXX: TruffleRuby's RegexpError exception message is different
-          if RUBY_ENGINE == 'truffleruby'
-            expect {
-              subject.parse_rule(rule)
-            }.to raise_error(OptionParser::InvalidArgument,"invalid argument: invalid Regexp: premature end of char-class (org.joni.exception.SyntaxException): /[abc/")
-          else
-            expect {
-              subject.parse_rule(rule)
-            }.to raise_error(OptionParser::InvalidArgument,"invalid argument: invalid Regexp: premature end of char-class: /[abc/")
-          end
+          expect {
+            subject.parse_rule(rule)
+          }.to raise_error(OptionParser::InvalidArgument,"invalid argument: invalid Regexp: premature end of char-class: /[abc/")
         end
       end
     end