how to specify "target" in ajax

form plugin and ajax,

i want to use form.serialize in cunjunction with ajax and don't know haow to specify where to put the servers "answer".

using ajaxSubmit i can specify this as "target". but how to specify it by using ajax.

(i need to manipulate the serialized string. inside the form are some buttons, if pressed some special variable shloud be send along with the other form data.)