how toggle between maven form another?

if i have maven form activated coming property, i interpretation another form wholly activated form activated?

e.g.

    <profile>
        <activation>
            <property>
                <name>myproperty</name>
                <value>value</value>
            </property>
        </activation>
        ...
    </profile>


    <profile>
        <activation>
            <property>
                <name>myproperty</name>
                <value></value> <!-- anything "value"  -->
            </property>
        </activation>
        ...
    </profile>