The attribute model is not defined

#0 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Catalog/Model/Layer/Filter/Abstract.php(239): Mage::throwException('The attribute m...')
#1 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/design/frontend/boilerplate/paciotti/template/page/html/breadcrumbs.phtml(105): Mage_Catalog_Model_Layer_Filter_Abstract->getAttributeModel()
#2 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(241): include('/var/www/vhosts...')
#3 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(272): Mage_Core_Block_Template->fetchView('frontend/boiler...')
#4 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(286): Mage_Core_Block_Template->renderView()
#5 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Page/Block/Html/Breadcrumbs.php(102): Mage_Core_Block_Template->_toHtml()
#6 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(919): Mage_Page_Block_Html_Breadcrumbs->_toHtml()
#7 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(637): Mage_Core_Block_Abstract->toHtml()
#8 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(581): Mage_Core_Block_Abstract->_getChildHtml('breadcrumbs', true)
#9 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/design/frontend/boilerplate/paciotti/template/page/html/header.phtml(94): Mage_Core_Block_Abstract->getChildHtml('breadcrumbs')
#10 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(241): include('/var/www/vhosts...')
#11 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(272): Mage_Core_Block_Template->fetchView('frontend/boiler...')
#12 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(286): Mage_Core_Block_Template->renderView()
#13 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(919): Mage_Core_Block_Template->_toHtml()
#14 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(637): Mage_Core_Block_Abstract->toHtml()
#15 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(581): Mage_Core_Block_Abstract->_getChildHtml('header', true)
#16 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/design/frontend/boilerplate/paciotti/template/page/1column.phtml(41): Mage_Core_Block_Abstract->getChildHtml('header')
#17 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(241): include('/var/www/vhosts...')
#18 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(272): Mage_Core_Block_Template->fetchView('frontend/boiler...')
#19 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Template.php(286): Mage_Core_Block_Template->renderView()
#20 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Block/Abstract.php(919): Mage_Core_Block_Template->_toHtml()
#21 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Model/Layout.php(555): Mage_Core_Block_Abstract->toHtml()
#22 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Controller/Varien/Action.php(390): Mage_Core_Model_Layout->getOutput()
#23 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Catalog/controllers/CategoryController.php(161): Mage_Core_Controller_Varien_Action->renderLayout()
#24 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Catalog_CategoryController->viewAction()
#25 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(254): Mage_Core_Controller_Varien_Action->dispatch('view')
#26 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Controller/Varien/Front.php(172): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
#27 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/code/core/Mage/Core/Model/App.php(354): Mage_Core_Controller_Varien_Front->dispatch()
#28 /var/www/vhosts/cesare-paciotti.com/httpdocs/app/Mage.php(686): Mage_Core_Model_App->run(Array)
#29 /var/www/vhosts/cesare-paciotti.com/httpdocs/index.php(109): Mage::run('', 'store')
#30 {main}