I have a JSP + SimpleFormController to find products from my database. In the form, I can chose a category of products in a dropdown list, that has been populated with items registered in the referenceData method. The results are displayed in the same JSP (containing the form), so as to be able to launch a new search. The first time the JSP is displayed, the dropdown list is well populated. When I submit a second time, I loose the reference data (categories). any idea about this ?