diff --git a/File.hs b/File.hs
--- a/File.hs
+++ b/File.hs
@@ -1,6 +1,6 @@
 {-# LANGUAGE OverloadedStrings #-}
 
-module File (mighty, progName) where
+module File (mighty, progName, fileMapper) where -- xxx
 
 import Control.Applicative
 import qualified Data.ByteString.Char8      as S
@@ -22,7 +22,7 @@
 progName = "Mighttpd"
 
 progVersion :: String
-progVersion = "0.4.2"
+progVersion = "0.4.3"
 
 progNameVersion :: String
 progNameVersion = progName ++ "/" ++ progVersion
@@ -41,35 +41,36 @@
 
 ----------------------------------------------------------------
 
-lookupFileMap :: URLMap -> URL -> Path
-lookupFileMap [] _          = None
-lookupFileMap ((from,to):xs) url
-    | from `isPrefixOf` url = toPath to $ drop (length from) url
+lookupFileMap :: URLMap -> URL -> Maybe (URL,ConvInfo)
+lookupFileMap [] _          = Nothing
+lookupFileMap (ent@(from,_):xs) url
+    | from `isPrefixOf` url = Just ent
     | otherwise             = lookupFileMap xs url
 
-toPath :: ConvInfo -> FilePath -> Path
-toPath (CIFile dir)   restPath  = File $ dir </> restPath
-toPath ci@(CICgi _ _) progParam = PathCGI CGI {
-    progPath    = prog
-    , scriptName  = scriptname
-    , pathInfo    = path
-    , queryString = query
-    }
+fileMapper :: URLMap -> URI -> Path
+fileMapper umap uri = case lookupFileMap umap url of
+    Nothing           -> None
+    Just (curl,cinfo) -> fileMapper' uri url curl cinfo
   where
-    (progParam',query)  = break (== '?') progParam
-    (prog',path)        = break (== '/') progParam'
-    prog = progDir ci </> prog'
-    scriptname = pathInURL ci </> prog'
+    url = unEscapeString . S.unpack . toURLPath $ uri -- without param
 
-fileMapper :: URLMap -> URI -> Path
-fileMapper umap uri = fileMapper' (lookupFileMap umap url)
+fileMapper' :: URI -> URL -> URL -> ConvInfo -> Path
+fileMapper' uri url curl cinfo = case cinfo of
+    CIFile dir      -> toFile (dir </> path0)
+    CICgi  dir path -> toCGI dir path
   where
-    url = unEscapeString . S.unpack . toURLwoPort $ uri
-    fileMapper' None                  = None
-    fileMapper' cgi@(PathCGI _)       = cgi
-    fileMapper' (File file)
-      | hasTrailingPathSeparator file = File $ file </> "index.html"
-      | otherwise                     = File file
+    path0 = drop (length curl) url
+    toFile path
+      | hasTrailingPathSeparator path = File (path </> "index.html")
+      | otherwise                     = File path
+    toCGI dir path = PathCGI CGI {
+        progPath    = dir </> prog
+      , scriptName  = path </> prog
+      , pathInfo    = pathinfo
+      , queryString = unEscapeString . S.unpack $ uriQuery uri
+      }
+      where
+        (prog,pathinfo) = break (== '/') path0
 
 fileGet :: FilePath -> Maybe (Integer,Integer) -> IO L.ByteString
 fileGet file Nothing = openFile file ReadMode >>= L.hGetContents
diff --git a/Mighttpd.hs b/Mighttpd.hs
--- a/Mighttpd.hs
+++ b/Mighttpd.hs
@@ -5,13 +5,14 @@
 import Config
 import Control.Monad
 import File
-import IO
 import LogMsg
 import Network.C10kServer
 import Network.Web.Server
 import System.Environment
 import System.Exit
+import System.IO
 import System.Posix.Daemonize (daemonize)
+import System.Posix.Signals
 import URLMap
 
 ----------------------------------------------------------------
@@ -77,6 +78,12 @@
 
 makeStartedHook :: Option -> IO ()
 makeStartedHook opt =
-  if opt_debug_mode opt
-  then initLog progName "" (opt_log_level opt) StdErr
-  else initLog progName (opt_syslog_facility opt) (opt_log_level opt) SysLog
+    if opt_debug_mode opt
+    then do
+        ignoreSigChild
+        initLog progName "" (opt_log_level opt) StdErr
+    else do
+        ignoreSigChild
+        initLog progName (opt_syslog_facility opt) (opt_log_level opt) SysLog
+  where
+    ignoreSigChild = installHandler sigCHLD Ignore Nothing
diff --git a/URLMap.hs b/URLMap.hs
--- a/URLMap.hs
+++ b/URLMap.hs
@@ -10,7 +10,7 @@
 data ConvInfo = CIFile String | CICgi { progDir :: String
                                       , pathInURL :: String
                                       }
-                deriving Show
+                deriving (Eq,Show)
 type URLMap = [(URL,ConvInfo)]
 
 parseURLMap :: String -> URLMap
diff --git a/mighttpd.cabal b/mighttpd.cabal
--- a/mighttpd.cabal
+++ b/mighttpd.cabal
@@ -1,5 +1,5 @@
 Name:                   mighttpd
-Version:                0.4.2
+Version:                0.4.3
 Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
 Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
 License:                BSD3
@@ -15,10 +15,13 @@
 Data-Files:             sample.conf sample.map
 Executable mighttpd
   Main-Is:              Mighttpd.hs
-  if impl(ghc >= 6.12)
-    GHC-Options:        -Wall -O2 -fno-warn-unused-do-bind
+  if impl(ghc >= 7)
+    GHC-Options:        -Wall -O2 -fno-warn-unused-do-bind -threaded
   else
-    GHC-Options:        -Wall -O2
+    if impl(ghc >= 6.12)
+      GHC-Options:        -Wall -O2 -fno-warn-unused-do-bind
+    else
+      GHC-Options:        -Wall -O2
   Ghc-Prof-Options:     -prof -auto-all -caf-all
   Build-Depends:        base >= 4 && < 5, parsec,
                         c10k, hslogger, webserver, bytestring, filepath,