diff --git a/Data/Encoding.hs b/Data/Encoding.hs
--- a/Data/Encoding.hs
+++ b/Data/Encoding.hs
@@ -50,6 +50,8 @@
 import Data.Encoding.KOI8R
 import Data.Encoding.KOI8U
 import Data.Encoding.GB18030
+import Data.Char
+import Text.Regex
 #endif
 
 -- | An untyped encoding. Used in 'System.IO.Encoding.getSystemEncoding'.
@@ -82,38 +84,189 @@
 #ifndef USE_HPC
 -- | Like 'encodingFromString' but returns 'Nothing' instead of throwing an error
 encodingFromStringMaybe :: String -> Maybe DynEncoding
-encodingFromStringMaybe "ASCII"		= Just $ DynEncoding ASCII
-encodingFromStringMaybe "UTF-8"		= Just $ DynEncoding UTF8
-encodingFromStringMaybe "UTF-16"	= Just $ DynEncoding UTF16
-encodingFromStringMaybe "UTF-32"	= Just $ DynEncoding UTF32
-encodingFromStringMaybe "KOI8-R"	= Just $ DynEncoding KOI8R
-encodingFromStringMaybe "KOI8-U"	= Just $ DynEncoding KOI8U
-encodingFromStringMaybe "ISO-8859-1"	= Just $ DynEncoding ISO88591
-encodingFromStringMaybe "ISO-8859-2"	= Just $ DynEncoding ISO88592
-encodingFromStringMaybe "ISO-8859-3"	= Just $ DynEncoding ISO88593
-encodingFromStringMaybe "ISO-8859-4"	= Just $ DynEncoding ISO88594
-encodingFromStringMaybe "ISO-8859-5"	= Just $ DynEncoding ISO88595
-encodingFromStringMaybe "ISO-8859-6"	= Just $ DynEncoding ISO88596
-encodingFromStringMaybe "ISO-8859-7"	= Just $ DynEncoding ISO88597
-encodingFromStringMaybe "ISO-8859-8"	= Just $ DynEncoding ISO88598
-encodingFromStringMaybe "ISO-8859-9"	= Just $ DynEncoding ISO88599
-encodingFromStringMaybe "ISO-8859-10"	= Just $ DynEncoding ISO885910
-encodingFromStringMaybe "ISO-8859-11"	= Just $ DynEncoding ISO885911
-encodingFromStringMaybe "ISO-8859-13"	= Just $ DynEncoding ISO885913
-encodingFromStringMaybe "ISO-8859-14"	= Just $ DynEncoding ISO885914
-encodingFromStringMaybe "ISO-8859-15"	= Just $ DynEncoding ISO885915
-encodingFromStringMaybe "ISO-8859-16"	= Just $ DynEncoding ISO885916
-encodingFromStringMaybe "CP1250"	= Just $ DynEncoding CP1250
-encodingFromStringMaybe "CP1251"	= Just $ DynEncoding CP1251
-encodingFromStringMaybe "CP1252"	= Just $ DynEncoding CP1252
-encodingFromStringMaybe "CP1253"	= Just $ DynEncoding CP1253
-encodingFromStringMaybe "CP1254"	= Just $ DynEncoding CP1254
-encodingFromStringMaybe "CP1255"	= Just $ DynEncoding CP1255
-encodingFromStringMaybe "CP1256"	= Just $ DynEncoding CP1256
-encodingFromStringMaybe "CP1257"	= Just $ DynEncoding CP1257
-encodingFromStringMaybe "CP1258"	= Just $ DynEncoding CP1258
-encodingFromStringMaybe "GB18030"	= Just $ DynEncoding GB18030
-encodingFromStringMaybe _		= Nothing
+encodingFromStringMaybe codeName = case (normalizeEncoding codeName) of
+    -- ASCII
+    "ascii"              -> Just $ DynEncoding ASCII
+    "646"                -> Just $ DynEncoding ASCII
+    "ansi_x3_4_1968"     -> Just $ DynEncoding ASCII
+    "ansi_x3.4_1986"     -> Just $ DynEncoding ASCII
+    "cp367"              -> Just $ DynEncoding ASCII
+    "csascii"            -> Just $ DynEncoding ASCII
+    "ibm367"             -> Just $ DynEncoding ASCII
+    "iso646_us"          -> Just $ DynEncoding ASCII
+    "iso_646.irv_1991"   -> Just $ DynEncoding ASCII
+    "iso_ir_6"           -> Just $ DynEncoding ASCII
+    "us"                 -> Just $ DynEncoding ASCII
+    "us_ascii"           -> Just $ DynEncoding ASCII
+    -- UTF-8
+    "utf_8"              -> Just $ DynEncoding UTF8
+    "u8"                 -> Just $ DynEncoding UTF8
+    "utf"                -> Just $ DynEncoding UTF8
+    "utf8"               -> Just $ DynEncoding UTF8
+    "utf8_ucs2"          -> Just $ DynEncoding UTF8
+    "utf8_ucs4"          -> Just $ DynEncoding UTF8
+    -- UTF-16
+    "utf_16"             -> Just $ DynEncoding UTF16
+    "u16"                -> Just $ DynEncoding UTF16
+    "utf16"              -> Just $ DynEncoding UTF16
+    -- UTF-32
+    "utf_32"             -> Just $ DynEncoding UTF32
+    -- KOI8-R
+    "koi8_r"             -> Just $ DynEncoding KOI8R
+    "cskoi8r"            -> Just $ DynEncoding KOI8R
+    -- KOI8-I
+    "koi8_u"             -> Just $ DynEncoding KOI8U
+    -- ISO-8859-1
+    "iso_8859_1"         -> Just $ DynEncoding ISO88591
+    "iso8859_1"          -> Just $ DynEncoding ISO88591
+    "8859"               -> Just $ DynEncoding ISO88591
+    "cp819"              -> Just $ DynEncoding ISO88591
+    "csisolatin1"        -> Just $ DynEncoding ISO88591
+    "ibm819"             -> Just $ DynEncoding ISO88591
+    "iso8859"            -> Just $ DynEncoding ISO88591
+    "iso_8859_1_1987"    -> Just $ DynEncoding ISO88591
+    "iso_ir_100"         -> Just $ DynEncoding ISO88591
+    "l1"                 -> Just $ DynEncoding ISO88591
+    "latin"              -> Just $ DynEncoding ISO88591
+    "latin1"             -> Just $ DynEncoding ISO88591
+    -- ISO-8859-2
+    "iso_8859_2"         -> Just $ DynEncoding ISO88592
+    "iso8859_2"          -> Just $ DynEncoding ISO88592
+    "csisolatin2"        -> Just $ DynEncoding ISO88592
+    "iso_8859_2_1987"    -> Just $ DynEncoding ISO88592
+    "iso_ir_101"         -> Just $ DynEncoding ISO88592
+    "l2"                 -> Just $ DynEncoding ISO88592
+    "latin2"             -> Just $ DynEncoding ISO88592
+    -- ISO-8859-3
+    "iso_8859_3"         -> Just $ DynEncoding ISO88593
+    "iso8859_3"          -> Just $ DynEncoding ISO88593
+    "csisolatin3"        -> Just $ DynEncoding ISO88593
+    "iso_8859_3_1988"    -> Just $ DynEncoding ISO88593
+    "iso_ir_109"         -> Just $ DynEncoding ISO88593
+    "l3"                 -> Just $ DynEncoding ISO88593
+    "latin3"             -> Just $ DynEncoding ISO88593
+    --ISO-8859-4
+    "iso_8859_4"         -> Just $ DynEncoding ISO88594
+    "iso8859_4"          -> Just $ DynEncoding ISO88594
+    "csisolatin4"        -> Just $ DynEncoding ISO88594
+    "iso_8859_4_1988"    -> Just $ DynEncoding ISO88594
+    "iso_ir_110"         -> Just $ DynEncoding ISO88594
+    "l4"                 -> Just $ DynEncoding ISO88594
+    "latin4"             -> Just $ DynEncoding ISO88594
+    --ISO-8859-5
+    "iso_8859_5"         -> Just $ DynEncoding ISO88595
+    "iso8859_5"          -> Just $ DynEncoding ISO88595
+    "csisolatincyrillic" -> Just $ DynEncoding ISO88595
+    "cyrillic"           -> Just $ DynEncoding ISO88595
+    "iso_8859_5_1988"    -> Just $ DynEncoding ISO88595
+    "iso_ir_144"         -> Just $ DynEncoding ISO88595
+    -- ISO-8859-6
+    "iso_8859_6"         -> Just $ DynEncoding ISO88596
+    "iso8859_6"          -> Just $ DynEncoding ISO88596
+    "arabic"             -> Just $ DynEncoding ISO88596
+    "asmo_708"           -> Just $ DynEncoding ISO88596
+    "csisolatinarabic"   -> Just $ DynEncoding ISO88596
+    "ecma_114"           -> Just $ DynEncoding ISO88596
+    "iso_8859_6_1987"    -> Just $ DynEncoding ISO88596
+    "iso_ir_127"         -> Just $ DynEncoding ISO88596
+    -- ISO-8859-7
+    "iso_8859_7"         -> Just $ DynEncoding ISO88597
+    "iso8859_7"          -> Just $ DynEncoding ISO88597
+    "csisolatingreek"    -> Just $ DynEncoding ISO88597
+    "ecma_118"           -> Just $ DynEncoding ISO88597
+    "elot_928"           -> Just $ DynEncoding ISO88597
+    "greek"              -> Just $ DynEncoding ISO88597
+    "greek8"             -> Just $ DynEncoding ISO88597
+    "iso_8859_7_1987"    -> Just $ DynEncoding ISO88597
+    "iso_ir_126"         -> Just $ DynEncoding ISO88597
+    -- ISO-8859-8
+    "iso_8859_8"         -> Just $ DynEncoding ISO88598
+    "iso8859_8"          -> Just $ DynEncoding ISO88598
+    "csisolatinhebrew"   -> Just $ DynEncoding ISO88598
+    "hebrew"             -> Just $ DynEncoding ISO88598
+    "iso_8859_8_1988"    -> Just $ DynEncoding ISO88598
+    "iso_ir_138"         -> Just $ DynEncoding ISO88598
+    -- ISO-8859-9
+    "iso_8859_9"         -> Just $ DynEncoding ISO88599
+    "iso8859_9"          -> Just $ DynEncoding ISO88599
+    "csisolatin5"        -> Just $ DynEncoding ISO88599
+    "iso_8859_9_1989"    -> Just $ DynEncoding ISO88599
+    "iso_ir_148"         -> Just $ DynEncoding ISO88599
+    "l5"                 -> Just $ DynEncoding ISO88599
+    "latin5"             -> Just $ DynEncoding ISO88599
+    -- ISO-8859-10
+    "iso_8859_10"        -> Just $ DynEncoding ISO885910
+    "iso8859_10"         -> Just $ DynEncoding ISO885910
+    "csisolatin6"        -> Just $ DynEncoding ISO885910
+    "iso_8859_10_1992"   -> Just $ DynEncoding ISO885910
+    "iso_ir_157"         -> Just $ DynEncoding ISO885910
+    "l6"                 -> Just $ DynEncoding ISO885910
+    "latin6"             -> Just $ DynEncoding ISO885910
+    -- ISO-8859-11
+    "iso_8859_11"        -> Just $ DynEncoding ISO885911
+    "iso8859_11"         -> Just $ DynEncoding ISO885911
+    "thai"               -> Just $ DynEncoding ISO885911
+    "iso_8859_11_2001"   -> Just $ DynEncoding ISO885911
+    -- ISO-8859-13
+    "iso_8859_13"        -> Just $ DynEncoding ISO885913
+    "iso8859_13"         -> Just $ DynEncoding ISO885913
+    -- ISO-8859-14
+    "iso_8859_14"        -> Just $ DynEncoding ISO885914
+    "iso8859_14"         -> Just $ DynEncoding ISO885914
+    "iso_8859_14_1998"   -> Just $ DynEncoding ISO885914
+    "iso_celtic"         -> Just $ DynEncoding ISO885914
+    "iso_ir_199"         -> Just $ DynEncoding ISO885914
+    "l8"                 -> Just $ DynEncoding ISO885914
+    "latin8"             -> Just $ DynEncoding ISO885914
+    -- ISO-8859-15
+    "iso_8859_15"        -> Just $ DynEncoding ISO885915
+    "iso8859_15"         -> Just $ DynEncoding ISO885915
+    "latin9"             -> Just $ DynEncoding ISO885915
+    "l9"                 -> Just $ DynEncoding ISO885915
+    -- ISO-8859-16
+    "iso_8859_16"        -> Just $ DynEncoding ISO885916
+    "iso8859_16"         -> Just $ DynEncoding ISO885916
+    "iso_8859_16_2001"   -> Just $ DynEncoding ISO885916
+    "iso_ir_226"         -> Just $ DynEncoding ISO885916
+    "l10"                -> Just $ DynEncoding ISO885916
+    "latin10"            -> Just $ DynEncoding ISO885916
+    -- CP1250
+    "cp1250"             -> Just $ DynEncoding CP1250
+    "windows_1250"       -> Just $ DynEncoding CP1250
+    -- CP1251
+    "cp1251"             -> Just $ DynEncoding CP1251
+    "windows_1251"       -> Just $ DynEncoding CP1251
+    -- CP1252
+    "cp1252"             -> Just $ DynEncoding CP1252
+    "windows_1252"       -> Just $ DynEncoding CP1252
+    -- CP1253
+    "cp1253"             -> Just $ DynEncoding CP1253
+    "windows_1253"       -> Just $ DynEncoding CP1253
+    -- CP1254
+    "cp1254"             -> Just $ DynEncoding CP1254
+    "windows_1254"       -> Just $ DynEncoding CP1254
+    -- CP1255
+    "cp1255"             -> Just $ DynEncoding CP1255
+    "windows_1255"       -> Just $ DynEncoding CP1255
+    -- CP1256
+    "cp1256"             -> Just $ DynEncoding CP1256
+    "windows_1256"       -> Just $ DynEncoding CP1256
+    -- CP1257
+    "cp1257"             -> Just $ DynEncoding CP1257
+    "windows_1257"       -> Just $ DynEncoding CP1257
+    -- CP1258
+    "cp1258"             -> Just $ DynEncoding CP1258
+    "windows_1258"       -> Just $ DynEncoding CP1258
+    -- GB18030
+    "gb18030"            -> Just $ DynEncoding GB18030
+    "gb18030_2000"       -> Just $ DynEncoding GB18030
+    -- defaults to nothing
+    _                    -> Nothing
+  where
+    normalizeEncoding s = map toLower $ subRegex sep s "_"
+    sep = mkRegex "[^0-9A-Za-z]+"
+
+
 
 -- | Takes the name of an encoding and creates a dynamic encoding from it.
 encodingFromString :: String -> DynEncoding
diff --git a/encoding.cabal b/encoding.cabal
--- a/encoding.cabal
+++ b/encoding.cabal
@@ -1,5 +1,5 @@
 Name:		encoding
-Version:	0.4
+Version:	0.4.1
 Author:		Henning Günther
 Maintainer:	h.guenther@tu-bs.de
 License:	BSD3
@@ -45,9 +45,9 @@
 
 Library
   if flag(splitBase)
-    Build-Depends:	bytestring, base >= 3, template-haskell, containers, array
+    Build-Depends:	bytestring, base >= 3, template-haskell, containers, array, regex-compat
   else
-    Build-Depends:	base < 3, template-haskell
+    Build-Depends:	base < 3, template-haskell, regex-compat
   Extensions:	TemplateHaskell,CPP,ExistentialQuantification,ForeignFunctionInterface
   C-Sources:	system_encoding.c
   Include-Dirs:	.