I had errors like "Command svn propget --recursive svn:externals resulted in an error: (RuntimeError)", after
a while i figure out how to fix this.

Just add (1) in file ./ruby/lib/ruby/gems/1.8/gems/piston-1.3.3/lib/piston/command.rb, right after  (2).

(1) command += ' #{RAILS_ROOT}'
(2) command = "svn #{args.join(' ')}" 

If u have more questions, just send me a mail to ravwar@gmail.com. 

Date: 2007-09-10 17:16
Sender: François Beausoleil

Hi,

It is impossible to refer to RAILS_ROOT, as Piston is not a Rails
tool: it is a general purpose tool.  It would be better to get
the full backtrace, what folder was the current working directory
and what was the target of your command instead.

Thanks !
François