FilterBuilder carries values across fields

[plech.d]

Hello,

I'm getting quite a strange behavior from my FilterBuilder. The use case is as follows:
a] Select a field and an operator and type in a value.
b] Use the drop-down box to switch to another field.

The FilterBuilder used in SmartGWT showcase deletes what has been typed in step a]. Mine doesn't. As I'm using my own extensions of FormItem, this is causing me trouble.

All I'm setting on my FilterBuilder is the following:

filterBuilder.setDataSource(dataDS);
filterBuilder.setShowAddButton(true);
filterBuilder.setShowSubClauseButton(true);
filterBuilder.setShowRemoveButton(true);
filterBuilder.setTopOperatorAppearance(TopOperatorAppearance.BRACKET);
filterBuilder.setSaveOnEnter(true);
filterBuilder.addSearchHandler(new SearchHandler() {
	
	@Override
	public void onSearch(FilterSearchEvent event) {
		filterer.filter(filterBuilder.getCriteria());
	}

});

- Tested in IE, Firefox, Chrome.
- SmartGWT 2.4
- GWT 2.1.1

Thanks in advance for a any ideas on this. Plech