Go into the query that is supplying the recordsource of the list box and give it a name. So, in the QBE grid it would look like this:
JOB ID:[refJOBID]
In SQL it would look like
SELECT YourTableName.refJOBID As JOB ID
I am not good with SQL directly so I use the QBE grid. With spaces in the name you may have to use single quotes or something 'JOB ID'