[ic] Scratch Variable in Shipping description?

[IC]

Hi folks,

Is there any way to get a scratch variable into the shipping description, I
cannot make it interpolate any tags in shipping.asc

I would like to set a scratch on the checkout page, eg:-

[if some test]
[tmp msg] Won't Ship Today [/tmp]
[/if]

If I try to add [scratch msg] to the shipping description in shipping.asc it
just prints the description and [scratch msg] not the actual variable.

Thanks,
Andy.