v.to.rast

I am digitizing some small archaeological sites in Vanderburgh County,
IN which are not being converted into raster cells in the v.to.rast
module. When I go back and enlarge the site in v.digit it is converted.
Is there any way outside of artificially enlarging the sites that I can
have these small sites converted by v.to.rast? Currently all my map
layers are based on a 30m square cell size.
Thanks,
Stephen Ball