Changing format for $RAD_REQUEST{'Event-Timestamp'} in Perl module

Hi, I need to change $RAD_REQUEST{'Event-Timestamp'} format before inserting to database. Looks like $RAD_REQUEST{'date:Event-Timestamp'}, $RAD_REQUEST{'integer:Event-Timestamp'} are not working. Is there any method to use date module or standard keywords in perl code or I should do it manually.