[GRASSLIST:4289] Problems with v.format - OSX

[mjc1 at soc.soton.ac.uk]

Hi, I have Grass5.7 with postgresql/postgis running on my Mac (10.3.5).   In 
the Grass tutorial, it talks about changing the default format to postgrass by 
using the command 'v.format'.  However, this doesn't appear to exist on my 
machine. Anyone else had similar problems and know how to solve?
Regards,
Michael