diff --git a/.github/workflows/coverage.yaml b/.github/workflows/coverage.yaml
index 542f018..b4f5ebc 100644
--- a/.github/workflows/coverage.yaml
+++ b/.github/workflows/coverage.yaml
@@ -14,7 +14,7 @@ jobs:
     name: ${{matrix.ruby}} on ${{matrix.os}}
     runs-on: ${{matrix.os}}-latest
     env:
-      BUNDLER_GEMFILE: ${{matrix.gemfile}}
+      BUNDLE_GEMFILE: ${{matrix.gemfile}}
     
     strategy:
       matrix:
diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index ee8fac6..610b74c 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -14,7 +14,7 @@ jobs:
     runs-on: ${{matrix.os}}-latest
     continue-on-error: ${{matrix.experimental}}
     env:
-      BUNDLER_GEMFILE: ${{matrix.gemfile}}
+      BUNDLE_GEMFILE: ${{matrix.gemfile}}
     
     strategy:
       matrix:
diff --git a/.gitignore b/.gitignore
index 09a72e0..6a0e22c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,5 @@
 /gems.locked
 /.covered.db
 /external
+
+*.lock
\ No newline at end of file
diff --git a/gems/gems.rb b/gems/gems.rb
new file mode 100644
index 0000000..aa0bd1f
--- /dev/null
+++ b/gems/gems.rb
@@ -0,0 +1,8 @@
+source "https://rubygems.org"
+
+gem "async-http"
+gem "bake-test"
+gem "bake-test-external"
+gem "sus"
+gem "sus-fixtures-async-http"
+gem "covered"
diff --git a/gems/rack-v1.rb b/gems/rack-v1.rb
index d820dd3..1f0c821 100644
--- a/gems/rack-v1.rb
+++ b/gems/rack-v1.rb
@@ -3,6 +3,6 @@
 # Released under the MIT License.
 # Copyright, 2022, by Samuel Williams.
 
-eval_gemfile("../gems.rb")
+eval_gemfile("gems.rb")
 
 gem "rack", "~> 1.0"
diff --git a/gems/rack-v2.rb b/gems/rack-v2.rb
index f2577f1..d774785 100644
--- a/gems/rack-v2.rb
+++ b/gems/rack-v2.rb
@@ -3,6 +3,6 @@
 # Released under the MIT License.
 # Copyright, 2022, by Samuel Williams.
 
-eval_gemfile("../gems.rb")
+eval_gemfile("gems.rb")
 
 gem "rack", "~> 2.0"
diff --git a/gems/rack-v3.rb b/gems/rack-v3.rb
index 9a3c0dd..715f65d 100644
--- a/gems/rack-v3.rb
+++ b/gems/rack-v3.rb
@@ -3,6 +3,6 @@
 # Released under the MIT License.
 # Copyright, 2022, by Samuel Williams.
 
-eval_gemfile("../gems.rb")
+eval_gemfile("gems.rb")
 
 gem "rack", "~> 3.0"
diff --git a/lib/protocol/rack/adapter.rb b/lib/protocol/rack/adapter.rb
index 70820a4..df289c5 100644
--- a/lib/protocol/rack/adapter.rb
+++ b/lib/protocol/rack/adapter.rb
@@ -11,7 +11,7 @@
 module Protocol
 	module Rack
 		module Adapter
-			if ::Rack::RELEASE >= "3"
+			if ::Rack.release >= "3"
 				IMPLEMENTATION = Rack3
 			else
 				IMPLEMENTATION = Rack2
diff --git a/lib/protocol/rack/adapter/rack2.rb b/lib/protocol/rack/adapter/rack2.rb
index cf5b16d..a05d22b 100644
--- a/lib/protocol/rack/adapter/rack2.rb
+++ b/lib/protocol/rack/adapter/rack2.rb
@@ -108,10 +108,12 @@ def wrap_headers(fields)
 						
 						if key.start_with?('rack.')
 							meta[key] = value
-						else
+						elsif value.is_a?(String)
 							value.split("\n").each do |value|
 								headers[key] = value
 							end
+						else
+							headers[key] = value
 						end
 					end
 					
diff --git a/test/protocol/rack/adapter.rb b/test/protocol/rack/adapter.rb
index 3c642cc..4fe75bc 100644
--- a/test/protocol/rack/adapter.rb
+++ b/test/protocol/rack/adapter.rb
@@ -75,6 +75,21 @@
 		end
 	end
 	
+	with 'non-string header value' do
+		let(:app) do
+			lambda do |env|
+				[200, {'x-custom' => 123}, ["Hello World!"]]
+			end
+		end
+		
+		let(:response) {client.get("/")}
+		
+		it "get valid response" do
+			expect(response.read).to be == "Hello World!"
+			expect(response.headers['x-custom']).to be == ['123']
+		end
+	end
+	
 	with 'REQUEST_URI', timeout: 1 do
 		let(:app) do
 			lambda do |env|