I tried to build a sparc kernel with UVM support and got the following:
   [ ... ]

looks like you didn't `make clean'.
   
   #options         SWAPPAGER       # swap paging
   #options         DEVPAGER        # paging to devices
   #options         VNODEPAGER      # paging to vnodes

these should not exist in a kernel config file.  my mistake that jason
corrected a couple of days ago.

   options         UVM             # UVM VM
   
   APOLLO:41: already have options `SWAPPAGER'
   APOLLO:42: already have options `DEVPAGER'
   APOLLO:43: already have options `VNODEPAGER'
   *** Stop.
   
   Which looks like they are being set elsewhere.

std.sparc.