Special price only applies to first option

[jonnyfilmboy]

I have a problem. I sell photographs that come in 4 sizes. Basically, small, medium, large and extra large.

 

Sml - $30

Med - $40

Lrg - $50

XLg - $100

 

I have my store set up so that there are 4 attributes for every normally $30 item. That way they get the pulldown to select the size they want for every photograph they order.

 

The problem I have is sales. I want to have a sale, 10% off. But the 10% is only knocked off the initial $30. Not the other sizes. So if someone orders an extra large photo, normally $100, they are charged $97 instead of $90. What happens is, 10% is taken off of $30, giving me $27, and the +$70 is added as normal (non sale). Thus the $97 charge instead of $100 - 10% = $90.

 

Is there a workaround for this? I know I can temporarily change the prices of the attributes by hand, but is there any way to apply a percent or amount off of an attribute?

 

Thanks in advance...