Coldfusion 7 query of queries

I am getting this error when trying to run a query of queries on a query constructed with QueryNew(): The value "" cannot be converted to a number

My hosting company recently upgraded to Coldfusion 7 and this is when the error began. It worked fine before this and I have not been able to figure out what to do to correct the issue.

I have dumped the query that I am constructing with QueryNew and beside some values being null the query looks fine. I don't think having some null fields should pose a problem.

Any ideas?