What is the name of your property editor class which performs the conversion? It looks like your configuration currently specifies the same class (TimeIntervalRange) for the convertible type and property editor in your CustomEditorConfigurer definition. The property editor should be specified as the value for the map entry in the customEditors property. For example:
Code:
<bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
<property name="customEditors">
<map>
<entry key="edu.vt.iddl.meval.versioning.TimeIntervalRange">
<bean class="edu.vt.iddl.meval.versioning.TimeIntervalRangeEditor" />
</entry>
</map>
</property>
</bean>