关于wsad 5.1 连接access 数据库的问题，急

我放到webshpere server不会报错
在wsad5.1 就报错
public static Connection getConnectionc() throws Exception {
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String url = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=e:\\ReportDemo.mdb";
conn = DriverManager.getConnection(url, "", "");
}
catch (ClassNotFoundException e) {
JOptionPane.showMessageDialog(null, e);
}
catch (SQLException e) {
JOptionPane.showMessageDialog(null, e);
}
return conn;
}
报下面错误
[10-6-19 6:26:21:430 GMT] 2c79f494 SystemErr R java.lang.NullPointerException
[10-6-19 6:26:21:430 GMT] 2c79f494 SystemErr R at sun.jdbc.odbc.JdbcOdbcDriver.initialize(JdbcOdbcDriver.java:436)
[10-6-19 6:26:21:430 GMT] 2c79f494 SystemErr R at sun.jdbc.odbc.JdbcOdbcDriver.connect(JdbcOdbcDriver.java:153)
[10-6-19 6:26:21:430 GMT] 2c79f494 SystemErr R at java.sql.DriverManager.getConnection(DriverManager.java:538)
[10-6-19 6:26:21:430 GMT] 2c79f494 SystemErr R at java.sql.DriverManager.getConnection(DriverManager.java:188)
[10-6-19 6:26:21:430 GMT] 2c79f494 SystemErr R at com.SqlDbQuery.DBConnection.main(DBConnection.java:69)