Index: resteasy-jaxrs/src/main/java/org/jboss/resteasy/plugins/providers/StringTextStar.java
===================================================================
--- resteasy-jaxrs/src/main/java/org/jboss/resteasy/plugins/providers/StringTextStar.java	(revision 834)
+++ resteasy-jaxrs/src/main/java/org/jboss/resteasy/plugins/providers/StringTextStar.java	(revision )
@@ -56,6 +56,8 @@
                        MultivaluedMap<String, Object> httpHeaders,
                        OutputStream entityStream) throws IOException
    {
-      entityStream.write(o.getBytes());
+      String charset = mediaType.getParameters().get("charset");
+      if (charset == null) charset = "UTF-8";
+      entityStream.write(o.getBytes(charset));
    }
 }
\ No newline at end of file