diff --git a/lib/protocol/http/headers.rb b/lib/protocol/http/headers.rb
index 76dcb5a..35160aa 100644
--- a/lib/protocol/http/headers.rb
+++ b/lib/protocol/http/headers.rb
@@ -345,7 +345,7 @@ def merge(headers)
 				"retry-after" => false,
 				"server" => false,
 				"transfer-encoding" => Header::TransferEncoding,
-				"user-agent" => false,
+				"user-agent" => Header::Split,
 				"trailer" => Header::Trailer,
 				
 				# Connection handling:
diff --git a/test/protocol/http/headers.rb b/test/protocol/http/headers.rb
index e5bb9b2..ed8c44e 100644
--- a/test/protocol/http/headers.rb
+++ b/test/protocol/http/headers.rb
@@ -281,6 +281,16 @@
 			
 			expect(headers["content-length"]).to be == "2"
 		end
+		
+		it "can merge multiple user-agent headers" do
+			headers.merge!([
+				["user-agent", "foobar/2000"],
+				["user-agent", "foobar/2001"],
+			])
+			
+			expect(headers["user-agent"]).to be == ["foobar/2000", "foobar/2001"]
+			expect(headers["user-agent"].to_s).to be == "foobar/2000,foobar/2001"
+		end
 	end
 	
 	with "#trailer!" do