The GRASS 5.0 internal sites format in "sites_list/" is:

easting|northing|[z|[d4|]...][#category_int] [ [@attr_text OR %flt] ... ]

such as:
739865.8|4279785.5|#2965 %396685 %194919 %160392 %10941 %2.473222 @"St.Louis" @MO @city

There can be many dimensions between pipes (|), but no #%@. 
There can be only one cat, preceded by #, then there may be 
many FP or text attributes.