//in module/controllers
//NOT in modules/controllers/Adminhtml
class MageB2B_Sublogin_SubloginController extends Mage_Adminhtml_Controller_Action


    <admin>
        <routers>
            <sublogin>
                <use>admin</use>
                <args>
                    <module>MageB2B_Sublogin</module>
                    <frontName>sublogin</frontName>
                </args>
            </sublogin>
        </routers>
    </admin>
    <adminhtml>
        <layout>
            <updates>
                <sublogin>
                    <file>sublogin.xml</file>
                </sublogin>
            </updates>
        </layout>
    </adminhtml>