Disregard previous picked date from next option

[LillaHjo]

Sorry about the title, not my first language...
I'm using date picker and have two fields, one for the date of arrival and one for departure. (see blow)
I would like to have the first one to control the second one, like if you pick feb 12 on arrival, you can only choose departure from Feb 13 and later.
Pasting the strings from the form. I´v tried to figure this out by reading here, but no success. Thanx for input. /Lars

Önskat incheckningsdatum (obligatorisk)
[date date-805 date-format:mm/dd/yy]

Önskat utcheckningsdatum (obligatorisk)
[date date-806 date-format:mm/dd/yy]