odoo/addons/project_issue/res_config_view.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>

        <record id="view_config_settings" model="ir.ui.view">
            <field name="name">Project Application</field>
            <field name="model">project.config.settings</field>
            <field name="type">form</field>
            <field name="inherit_id" ref="project.view_config_settings"/>
            <field name="arch" type="xml">
                <group name="support" position="after">
                	<newline/>
                    <field name="fetchmail_issue"/>
                    <group attrs="{'invisible': [('fetchmail_issue','=',False)]}">
                    	<button colspan="2" type="object" name="configure_fetchmail_issue" string="Configure" icon="gtk-execute"/>
                    </group>
                </group>
            </field>
        </record>

    </data>
</openerp>