SQL0104 Token (fieldname) not valid from .NET data provider

I'm working on an ASP.NET application that uses our IBM i as the database server. The i is running 6.1. When running on my local PC (Win7 x64, Client Access 6.1), I'm getting the expected results. My queries are running properly. However, I just deployed the app to the QA web server, and am getting the weirdest SQL error ever. That machine is running Server 2008 x64 with Client Access V5R4 installed.

My SQL statement looks like this:

SELECT INVID, INVCONO, INVUNNO, INVNUM, INVDATE, INVVENDNM, INVFOODAMT, INVNFAMT,
INVCOMMENT, INVACCT, INVVHVECO, INVVHIREF, INVVHAUDT, INVVHVEND, INVIMS, INVVEND
FROM FINPINV
WHERE invcono = @cono
AND invunno = @unno
AND invvhiref IS NULL

I then add the parameters in and run the query. I get:
Token INVUNNO was not valid. Valid tokens: FOR SKIP WITH FETCH ORDER UNION
EXCEPT OPTIMIZE.

I then simplify the query to:

SELECT * FROM FINPINV
WHERE invcono = @cono
AND invunno = @unno
AND invvhiref IS NULL

This works as expected on the QA box. However, the SELECT * will probably not pass a code review, and it's not ideal anyway. Since I have fields specified in all of my SQL statements across 10 .cs files, I don't want to go back and change all of them. I haven't gotten it working well enough in QA yet to try the UPDATE or INSERT queries.

So my questions:

* Is this caused by running the V5R4 Client against a 6.1 server?

* Is there some configuration setting somewhere that would fix it?

* Should I spend my time correcting this on the QA box, when the production server has Client 6.1 already installed? (The production box was built to my specs.)

Any advice would be appreciated.

Thanks,

John Maassel
Programmer/Analyst
Bob Evans Farms, Inc
john_maassel@xxxxxxxxxxxx<mailto:john_maassel@xxxxxxxxxxxx>

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