How to insert Chinese (big5) through JDBC?

Hi all,
   I encounter problem when inserting Chinese.
   These are my setting:
   - postgresql 7.3 (database encoding: "SQL_ASCII")
   - JDBC: pg73jdbc2.jar
   - Tomcat 4.1.24
   - JSP/Servlet/Java Bean

   insert into table1 values('¤@¤G¤T') // chinese cannot display here...
   Insert Chinese words are ok. But when I select the record, there were wrong sth. like '? ?³æ '
   The sql statement is in big5 format because I write it in a log file.

   I've tried using charset like this. Not knowing why. All fail...
   jdbc:postgresql://202.71.201.252:5432/CA_care?charSet=ISO-8859-1
   jdbc:postgresql://202.71.201.252:5432/CA_care?charSet=SQL_ASCII
   jdbc:postgresql://202.71.201.252:5432/CA_care?charSet=UTF-8
   jdbc:postgresql://202.71.201.252:5432/CA_care?charSet=Big5
  
   Any idea.

Best Regards,
     Eric Tan