JDBC rs.getString() encoding problem

Hello,
  I write a Java Servlet program which use rs.getString()
to retrive data (UTF-8 encoded data). The char I got is
?(65533).  But if I use a Java AP to retrive the data,
the return char is OK.
  I guess there are some environment variable which
will affect the String return by rs.getString(). Somebody
can give me a hint?   Thanks in advance.

Bruce