Linked Server

Hi,
I created a linked server.
And facing the Err as follows when I tried to query the table from oracle DB thorugh the linked server.
Could be of very great help .....if you provide me some suggestion which avoids err and fetches the table as needed.

EXEC sp_addlinkedserver
'TEST_LNK_SRV', 'Oracle',
'MSDAORA', 'oracleDW'

EXEC sp_addlinkedsrvlogin 'TEST_LNK_SRV', false,
'sowv', 'RDATA', 'pwd'

till her..it executed and created the linked server named TEST_LNK
And When I tried the below qry

select * from openquery(TEST_LNK_SRV,'select * from ASUP_HDD.dbo.t_checkCondition')

ERR:
OLE DB provider "MSDAORA" for linked server "TEST_LNK_SRV" returned message "ORA-01004: default username feature not supported; logon denied
".
Msg 7399, Level 16, State 1, Line 1
The OLE DB provider "MSDAORA" for linked server "TEST_LNK_SRV" reported an error. Authentication failed.
Msg 7303, Level 16, State 1, Line 1
Cannot initialize the data source object of OLE DB provider "MSDAORA" for linked server "TEST_LNK_SRV".

Thanks in advance,
Sowmya

And what does it have to do with SQL Assistant product?