Answer
The field used to display a value cannot be changed.
ArcIMS 3.0 Java looks for one of these fields: name, id, or code. The search is done in that order of priority, and is not case sensitive. If a field is not found, the Java application uses the temporary name NewFeatureN; where N is an integer starting at 1 and incrementing itself by 1 for each feature.
ArcIMS 3.1 uses the same method for selecting a field for the Identify window; however, if a field is not found, the first field in the attribute table is used.
Note:
Java Viewers: You can create a field with the string NAME in it, and assign it an alias in the setQueryResultFields function in the default.js file.