diff --git a/user/super/com/google/gwt/emul/java/nio/charset/Charset.java b/user/super/com/google/gwt/emul/java/nio/charset/Charset.java
index aaa21e3..615b5f7 100644
--- a/user/super/com/google/gwt/emul/java/nio/charset/Charset.java
+++ b/user/super/com/google/gwt/emul/java/nio/charset/Charset.java
@@ -22,7 +22,6 @@
 import java.util.SortedMap;
 import java.util.TreeMap;
 import javaemul.internal.EmulatedCharset;
-import javaemul.internal.NativeRegExp;
 
 /**
  * A minimal emulation of {@link Charset}.
@@ -60,11 +59,7 @@
       return EmulatedCharset.UTF_8;
     }
 
-    if (new NativeRegExp("^[A-Za-z0-9][\\w-:\\.\\+]*$").test(charsetName)) {
-      throw new UnsupportedCharsetException(charsetName);
-    } else {
-      throw new IllegalCharsetNameException(charsetName);
-    }
+    throw new UnsupportedCharsetException(charsetName);
   }
 
   private final String name;
diff --git a/user/test/com/google/gwt/emultest/java/nio/charset/CharsetTest.java b/user/test/com/google/gwt/emultest/java/nio/charset/CharsetTest.java
index ad6f887..8811f06 100644
--- a/user/test/com/google/gwt/emultest/java/nio/charset/CharsetTest.java
+++ b/user/test/com/google/gwt/emultest/java/nio/charset/CharsetTest.java
@@ -17,7 +17,6 @@
 package com.google.gwt.emultest.java.nio.charset;
 
 import com.google.gwt.emultest.java.util.EmulTestBase;
-
 import java.nio.charset.Charset;
 import java.nio.charset.IllegalCharsetNameException;
 import java.nio.charset.UnsupportedCharsetException;
@@ -49,22 +48,22 @@
     try {
       Charset.forName("");
       fail();
-    } catch (IllegalCharsetNameException expected) {
+    } catch (IllegalCharsetNameException | UnsupportedCharsetException expected) {
     }
     try {
       Charset.forName("!@#$");
       fail();
-    } catch (IllegalCharsetNameException expected) {
+    } catch (IllegalCharsetNameException | UnsupportedCharsetException expected) {
     }
     try {
       Charset.forName("_UTF_8");
       fail();
-    } catch (IllegalCharsetNameException expected) {
+    } catch (IllegalCharsetNameException | UnsupportedCharsetException expected) {
     }
     try {
       Charset.forName("UTF_8#");
       fail();
-    } catch (IllegalCharsetNameException expected) {
+    } catch (IllegalCharsetNameException | UnsupportedCharsetException expected) {
     }
   }