Change language in Wordpress plugin - NEED TO START NOW

I need help to change the language in the wordpress plugin: [login to view URL] Extra information about the plugin from the author: [login to view URL] Basicly i need the month names and the weekday names in danish in frontend and backend., and i cant figure out how to translate that part. I can get the rest.. so its just The weekdaynames, and the month names i need changed. Also i need it to display 24H times in stead of PM/AM. I want you to work on the calendar on your own site, and when we agree that it looks right the project is accepted as finished. I need this ASAP (max 24 hours from now) If you have done other plugins before please show a link in a PM. Best price wins the project.