Highstock navigator padding issue

Highstock navigator padding issue

I am using Highstock charts with single series having flags on it where
x-axis is 'datetime' type and y-axis is any numerical value. Now initially
when chart loads I provide bit of padding on x-axis using attribute "max"
so that end point doesn't touch the edge (which is working fine) but as I
drag the navigator, the padding gets lost and the point touches the edge.
Is there any way of maintaining that padding on graph line even after I
drag the navigator?
Any help would be greatly appreciated...