JSP中数据库插入错误！

写一个查询语句就没有错误
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String user = "";
String password = "";
Connection conn = DriverManager.getConnection("jdbc:odbc:data",user,password);
Statement stmt = conn.createStatement();
ResultSet resultset;

resultset = stmt.executeQuery("select * from user");
while(resultset.next()){
out.println(resultset.getString("Name"));
out.println(" ");
out.println(resultset.getString("Password"));
out.println("<br>");
}
而插入一个记录
String m_name = request.getParameter("name");
String m_password = request.getParameter("password");

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String user = "";
String password = "";
Connection conn = DriverManager.getConnection("jdbc:odbc:data",user,password);
Statement stmt = conn.createStatement();
String sql = "Insert into user(Name,Password) values('"+m_name+"','"+m_password+")";
stmt.executeUpdate(sql);

报错如下：
javax.servlet.ServletException: [Microsoft][ODBC Microsoft Access Driver] ???????? ?????? ''null)' ??
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:673)
org.apache.jsp.database.reg_005fmanage_jsp._jspService(reg_005fmanage_jsp.java:72)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)

这是什么原因？