Quantity Discount Mod vs coupon codes

[stlnyc]

I used both the quantity discount mod and coupons on my site. When customers pick 12 or more items from our store they automatically get 15% off.

We also are offering a coupon to new customers with a 10% off coupon.

Is there a way to prevent using both at the same time?

[swguy]

You have to write code; nothing is built in.

[BullTamer]

Has anyone been able to figure this one out?

Thanks,

Bull