Converting UTM maps from NAD27 to NAD83

Dear GRASS'ers:

  We would like to convert our existing GRASS UTM maps from NAD27 to NAD83... does anybody know how we could do that in GRASS??? The problem is our GRASS
maps are in NAD27 format and we are trying to bring over ARC/INFO maps that are
in NAD83. Any tips/hints/pointers/suggestions would be most helpful.

Thank you,

Shane.

amante@grouse.pnl.gov
Battelle Pacific Northwest Laboratories
Richland, WA 99352 USA