Problem with where files are copied for Dual Boot

Hi, I'm installing RC-1 to dual-boot with XP Home. I've got my partitions as
I want and have selected my 20GB y: partition in the installer (which is
running from inside XP - no DVD burner here). However, I notice that during
"copying windows files", files are actually added to my main 80GB c:
partition.

I want to know if this is normal, had installation got the partition right
and is just using c: for storage - or will it go ahead and install on c:
rather than y:.

Thanks for your help.