how to reset a form

[tubin gen]

My application is using hibernate and wicket  , I am trying to reset my form
, My form model is hibernate entity  and its LoadableDetachableModel .  In
order to reset my form I added ajax button  , hoping to call form.clearInput
()  in the onSubmit , but realized that before   the onSubmit ,  form
updates model  and becasue  I am using hibernate open view session filter,
my entity   is persisted  automatically , so instead of resetting I am
persisting  the form   model , please help me how can I rest my form ?