[web2py] powertable problem

[ceriox]

hi all,
i'm testing powertable plugin but i can't make it work correctly (i
don't have the "green plus" icon for expand the row of a table item)
where is the problem?

this is my code:

def index():
    """
    Test powerTable
    """
    table = plugins.powerTable
    table.datasource = db.auth_user
    table.dtfeatures['sScrollY'] = '100%'
    table.dtfeatures['sPaginationType'] = 'full_numbers'
    table.headers = 'labels'
    table.keycolumn = 'auth_user.id'
    table.columns =
['auth_user.username','auth_user.first_name','auth_user.last_name']
    table.showkeycolumn = False
    table.uitheme = 'redmond'
    table.extra = dict(
 
details={'detailscallback':URL('myfunction.load')}
                       )

    table = table.create()

    return locals()

def myfunction():
    """
    return a custom object to be inserted in detail for table
    """
    obj = DIV()
    obj.append(H1('Title for my details'))
    obj.append(SQLFORM(db.auth_user))
    obj.append(SQLTABLE(db(db.auth_user).select()))

    return locals()