I've set up my system to dual boot 1.5.2 and current. The boot program boots wd1a:netbsd by default, which is the 1.5.2 kernel. Interactively I can cause it to boot wd1e:netbsd which is the current kernel. How do I set the default so the boot program boots wd1e:netbsd instead of wd1a:netbsd?