function Deprecated

Hi,

I enable the wp-debug in my customer web site and I have these messages:

– Deprecate: Function create_function() is deprecated in /home/XXXX/public_html/wp-content/plugins/download-manager/modules/widgets.php on line 501
– Warning: Cannot modify header information – headers already sent by (output started at /home/xxx/public_html/wp-content/plugins/download-manager/modules/widgets.php:501) in /home/xxxx/public_html/wp-includes/functions.php on line 6221

Is it possibile to corret them?

thank you