Job Design change for Left outer join

[rajudx]

One datastage job is designed with 3 input oracle stages and one join stage and one output stage (sequential stage)

o1------------
->
o2----------> Join (Left Outer)---------------->Output
^
o3---------------

In Join stage join type defined as left outer join and key column is C1 and all input stage having different types of meta data expect key column..
Due to some data issue on o3 input we need to make a change in join condition,if any key column will come from o3 it should go to go output column without checking value on o1.
I think any kind of join type won't work and can some one please suggest for design change which we can bring the record from o3 even if key value is not matching with 01 key value.

Thanks,
Raju.

[ray.wurlod]

All inputs to one Join stage must specify the same join key. If the join key is changing, use cascaded Join stages.

[Sampath]

First u do join with 1 and 2 table after use one more join for joining 1&2 output with 3 table