there should be constraints checking for uniques of formfield names per usecase
fixed: the form fields now have the action name prepended to their name, this works fine, however, this might lead to duplicates when you have the same parameter name on different actions with the same name
until this is discussed with others I will not close this issue
the last major bpm4struts update also addressed this issue, this should be fixed, reopen it in case you find some special case in which you think the behavior is funky