exception Mage_Core_Exception with message Invalid block type: Mage_Intrepiaorders_Block_Intrepiaorders in /www/xxxxxxx/htdocs/app/Mage.php:595
Stack trace:
#0 /www/xxxxxxx/htdocs/app/code/core/Mage/Core/Model/Layout.php(495): Mage::throwException('Invalid block t...')
#1 /www/xxxxxxx/htdocs/app/code/core/Mage/Core/Model/Layout.php(437): Mage_Core_Model_Layout->_getBlockInstance('intrepiaorders/...', Array)
#2 /www/xxxxxxx/htdocs/app/code/core/Mage/Core/Model/Layout.php(472): Mage_Core_Model_Layout->createBlock('intrepiaorders/...', 'intrepia')
#3 /www/xxxxxxx/htdocs/app/code/core/Mage/Core/Model/Layout.php(239): Mage_Core_Model_Layout->addBlock('intrepiaorders/...', 'intrepia')
#4 /www/xxxxxxx/htdocs/app/code/core/Mage/Core/Model/Layout.php(205): Mage_Core_Model_Layout->_generateBlock(Object(Mage_Core_Model_Layout_Element), Object(Mage_Core_Model_Layout_Element))
#5 /www/xxxxxxx/htdocs/app/code/core/Mage/Core/Model/Layout.php(210): Mage_Core_Model_Layout->generateBlocks(Object(Mage_Core_Model_Layout_Element))
...............

<?xml version="1.0"?>
<config>
    <global>
        <modules>
            <Abc_IntrepiaOrders>
                <version>1.0.0</version>
            </Abc_IntrepiaOrders>
        </modules>
        <helpers>
            <abc_intrepiaOrders>
                <!-- Helper definition needed by Magento -->
                <class>Mage_Core_Helper</class>
            </abc_intrepiaOrders>
        </helpers>
        <helpers>
            <abc_intrepiaOrders>
                <class>Abc_IntrepiaOrders_Helper</class>
            </abc_intrepiaOrders>
        </helpers>
        <blocks>
            <intrepiaOrders>
                <rewrite>
                    <intrepiaOrders>Abc_IntrepiaOrders_Block</intrepiaOrders>
                </rewrite>
            </intrepiaOrders>
        </blocks>
    </global>
    <admin>
        <routers>
            <adminhtml>
                <args>
                    <modules>
                        <abc_intrepiaOrders before="Mage_Adminhtml">Abc_IntrepiaOrders_Adminhtml</abc_intrepiaOrders>
                    </modules>
                </args>
            </adminhtml>
        </routers>
    </admin>
    <adminhtml>
        <layout>
            <updates>
                <abc>
                    <file>intrepiaorders.xml</file>
                </abc>
            </updates>
        </layout>
    </adminhtml>
    <frontend>
        <routers>
            <intrepiaorders>
                <use>standard</use>
                <args>
                    <module>Abc_IntrepiaOrders</module>
                    <frontName>intrepiaorders</frontName>
                </args>
            </intrepiaorders>
        </routers>
        <layout>
            <updates>
                <intrepiaorders>
                    <file>tests.xml</file>
                </intrepiaorders>
            </updates>
        </layout>
    </frontend>
</config>

<?xml version="1.0"?>
<layout version="0.1.0">
    <intrepiaorders_index_index>
        <reference name="root">
            <action method="setTemplate">
                <template>page/1column.phtml</template>
            </action>
        </reference>
        <reference name="content">
            <block type="intrepiaorders/intrepiaorders" name="intrepia" template="intrepiaorders/intrepiaorders.phtml" />
        </reference>
    </intrepiaorders_index_index>
</layout>

class Abc_IntrepiaOrders_IndexController extends Mage_Core_Controller_Front_Action {
    public function indexAction() {
        $this->loadLayout(array('default'));
        $this->renderLayout();
    }
}

class Abc_IntrepiaOrders_Block_IntrepiaOrders extends Mage_Core_Block_Template {
    // necessary methods
}

<block type="intrepiaorders/intrepiaorders" name="intrepia" template="intrepiaorders/intrepiaorders.phtml" />

<block type="intrepiaOrders/intrepiaOrders" name="intrepia" template="intrepiaorders/intrepiaorders.phtml" />

<blocks>
            <intrepiaOrders>
                <rewrite>
                    <intrepiaOrders>Abc_IntrepiaOrders_Block_IntrepiaOrders</intrepiaOrders>
                </rewrite>
            </intrepiaOrders>
        </blocks>