Just two days ago I wrote about S3TC-compressed textures and that it is a little bit tricky for amd64 users to get the correct libraries installed. Since then I've been in contact with Christian Marillat, the guy behind debian-multimedia.org and he immediately responded with uploading ia32-libs-libtxc-dxtn0 to make it easier to install the 32 bit variant of libtxc_dxtn0 on 64 bit platforms.
A big Thank You! to Christian! And if you find his service helpful, consider donating to him (I can only guess at the amount of traffic he gets, especially since a lot of people certainly don't use one of the mirrors). (Just a short disclaimer: Christian didn't ask me to put the donation request in this post, in fact he'll only know about it, as soon as this goes online.)
I'll add an Suggests: in the next upload of wine-unstable to the server on libtxc-dxtn0/ia32-libs-libtxc-dxtn0 so people'll have an easier time to get S3TC working. But again: before installation: make sure it is legal for you to install the library.