iBatis合并语句-未确定值

Question

我正在尝试在我的iBatis 2 xml文件中使用合并语句。合并（更新/插入）如下所示：

<update id="insertTaxPer" parameterClass="per">
    MERGE INTO tax_retry USING DUAL 
        ON (per_id= #perId#) 
        WHEN MATCHED THEN 
            UPDATE SET
            <isNotNull property="perTitle">
                    per_title = #perTitle#  
            </isNotNull>
        WHEN NOT MATCHED THEN    
        INSERT INTO PE_AUTH_REENTRY(
            per_id,
            per_no,
            per_title)
        VALUES( 
            #perId#,
            #perNo#,
            #perTitle#
        )
    </update>


Getting the below error

    Caused by: org.springframework.jdbc.BadSqlGrammarException: SqlMapClient operation; bad SQL grammar []; nested exception is com.ibatis.common.jdbc.exception.NestedSQLException:   
--- The error occurred while applying a parameter map.  
--- Check the insertRenTryPublication-InlineParameterMap.  
--- Check the statement (update failed).  
--- Cause: java.sql.SQLException: ORA-00926: missing VALUES keyword
 while executing  sql: 
MERGE INTO tax_retry USING dual ON ( per_id =?)
WHEN MATCHED THEN UPDATE SET per_title =? 
WHEN NOT MATCHED THEN       
INSERT INTO tax_retry(    per_id,    per_no,    per_title)   
VALUES(     ?,    ?,    ?)   with parameters: 
[53961, 53961, TESTER]

我无法升级到更高版本或mybatis，因为它是旧版应用程序。有输入吗？