Checkboxes by line break separation within notification emails

Hi,

I have a question about the checkbox value items that I receive in my mail after someone fills in my contact from 7. If someone has checked these three boxes in the form:

? CHECKBOX1
? CHECKBOX2
? CHECKBOX3

Then in my mail they appear as: CHECKBOX1, CHECKBOX2, CHECKBOX3

However I would like to change the comma separation into line breaks.

I really need this, would you possibly add a snippet of code?

Thanks!