diff --git a/http_parser.rl b/http_parser.rl
index 0d8fa50..5d27074 100644
--- a/http_parser.rl
+++ b/http_parser.rl
@@ -387,11 +387,11 @@ do {                                                                 \
   chunk_ext_val = token*;
   chunk_ext_name = token*;
   chunk_extension = ( ";" " "* chunk_ext_name ("=" chunk_ext_val)? )*;
-  last_chunk = "0"+ chunk_extension CRLF;
-  chunk_size = (xdigit* [1-9a-fA-F] xdigit*) $add_to_chunk_size;
+  last_chunk = "0"+ ( chunk_extension | " "+) CRLF;
+  chunk_size = (xdigit* [1-9a-fA-F] xdigit* ) $add_to_chunk_size;
   chunk_end  = CRLF;
   chunk_body = any >skip_chunk_data;
-  chunk_begin = chunk_size chunk_extension CRLF;
+  chunk_begin = chunk_size ( chunk_extension | " "+ ) CRLF;
   chunk = chunk_begin chunk_body chunk_end;
   ChunkedBody := chunk* last_chunk trailing_headers CRLF @end_chunked_body;
 
diff --git a/test.c b/test.c
index ba8329f..0adf7e5 100644
--- a/test.c
+++ b/test.c
@@ -362,7 +362,34 @@ const struct message responses[] =
   ,.num_headers= 0
   ,.headers= {}
   ,.body= ""
-}
+  }
+
+, {.name="200 trailing space on chunked body"
+  ,.type= HTTP_RESPONSE
+  ,.raw= "HTTP/1.1 200 OK\r\n"
+         "Content-Type: text/plain\r\n"
+         "Transfer-Encoding: chunked\r\n"
+         "\r\n"
+         "25  \r\n"
+         "This is the data in the first chunk\r\n"
+         "\r\n"
+         "1C\r\n"
+         "and this is the second one\r\n"
+         "\r\n"
+         "0  \r\n"
+         "\r\n"
+  ,.should_keep_alive= TRUE
+  ,.status_code= 200
+  ,.num_headers= 2
+  ,.headers=
+    { {"Content-Type", "text/plain" }
+    , {"Transfer-Encoding", "chunked" }
+    }
+  ,.body =
+         "This is the data in the first chunk\r\n"
+         "and this is the second one\r\n"
+
+  }
 
 , {.name= NULL } /* sentinel */
 };
@@ -653,7 +680,7 @@ test_scan (const struct message *r1, const struct message *r2, const struct mess
 
       http_parser_execute(&parser, buf3, buf3_len);
 
-      assert(! http_parser_has_error(&parser));
+      assert(!http_parser_has_error(&parser));
 
       assert(3 == num_messages);