Incorrect results obtained while running Sql query through S

Hi, 

I have read the Sql reference of Salesforce data direct driver and built the following query and execute through Salesforce datadirect driver.

select T1.SYS_NAME,
unitprice,
totalprice,
Listprice,
T2.closedate,
T2.FiscalYear,
T2.Fiscalquarter,
T2.Stagename,
T3.sys_name,
T4.firstname,
T4.Lastname,
T6.SYS_NAME
from opportunitylineitem T1 left outer join opportunity T2 on T1.opportunityid=T2.ROWID
Left outer join Account T3 on T2.Accountid=T3.ROWID
Left outer join User T4 on T2.sys_ownerid=T4.ROWID
Left outer join Pricebookentry T5 on T1.pricebookentryid=T5.Rowid
Left outer join Product2 T6 on T5.Product2id=T6.Rowid

The output has  T1.SYS_NAME and T6.SYS_NAME columns as same values, whereas they are both different columns from two different tables. Please provide inputs on how to get the SYS_NAME from respective tables of Salesforce.

Thanks,

Vinay