diff --git a/Text/NamePrep.hs b/Text/NamePrep.hs
--- a/Text/NamePrep.hs
+++ b/Text/NamePrep.hs
@@ -2,10 +2,11 @@
 
 import Text.StringPrep
 
-namePrepProfile :: StringPrepProfile
-namePrepProfile = Profile {
-	maps = [b1,b2],
-	shouldNormalize = True,
-	prohibited = [c12,c22,c3,c4,c5,c6,c7,c8,c9],
-	shouldCheckBidi = True
+namePrepProfile :: Bool -> StringPrepProfile
+namePrepProfile allowUnassigned =
+	Profile {
+		maps = [b1,b2],
+		shouldNormalize = True,
+		prohibited = (if allowUnassigned then [] else [a1]) ++ [c12,c22,c3,c4,c5,c6,c7,c8,c9],
+		shouldCheckBidi = True
 	}
diff --git a/Text/StringPrep.hs b/Text/StringPrep.hs
--- a/Text/StringPrep.hs
+++ b/Text/StringPrep.hs
@@ -2,6 +2,7 @@
 module Text.StringPrep (
 StringPrepProfile(..),
 runStringPrep,
+a1,
 b1,b2,
 c11,c12,c21,c22,c3,c4,c5,c6,c7,c8,c9
 ) where
@@ -159,4 +160,4 @@
 	range '\xFE76' '\xFEFC']
 
 #include "l.hs"
-
+#include "a1.hs"
diff --git a/stringprep.cabal b/stringprep.cabal
--- a/stringprep.cabal
+++ b/stringprep.cabal
@@ -1,5 +1,5 @@
 Name: stringprep
-Version: 0.1
+Version: 0.1.1
 Description: Implements the "StringPrep" algorithm
 Synopsis: Implements the "StringPrep" algorithm
 License: BSD3