sync with lightning

Hello,

I use my gmx account now for half a year, and i nust say: it is a pleasure to work with.
I only have a question: can your team make any syncronising system to sync my organiser wiht my calender in my Thunderbird Lightning calendar?
With the Gmail calendar it is possible, because there is an add-on. I don't know how it will works with the gmx organiser but it would be nice if there is any possibility to make one.
This is no comment but only a suggestion.
Thanks for this time and it would be nice to hear from you.

Kind regards,

millman