full width header but fixed smaller forum width ...how to do?

[kurti]

hi,
i have version 3.7.4
and would like to use a header image that has a larger width (1280px)
than the forum (fixed to 1000px).

my problem is that when i enter the image
via Style Manager/Image Paths/Title Image
it acts like a normal grafik ...making the browser scroll
when the window is smaller than the image.

it should be acting like a background image...
so that the parts that are beyond the size of the window simply disappear.

can anyone please tell me how this could be done?

--------------- Added [DATE]1229039263[/DATE] at [TIME]1229039263[/TIME] ---------------

problem solved