syntax error, unexpected tIDENTIFIER, expecting $end

[rtacconi]

A medium complex command (safe mode disable) is causing this error

ruby-1.9.3-preview1 :047 > rbox.execute "echo -e "new_passwd\nnew_passwd" | passwd a_user"
SyntaxError: (irb):47: syntax error, unexpected tIDENTIFIER, expecting $end
rbox.execute "echo -e "new_passwd\nnew_passwd" | passwd a_user"
^
from /Users/riccardotacconi/.rvm/rubies/ruby-1.9.3-preview1/bin/irb:16:in <main>' ruby-1.9.3-preview1 :048 > rbox.execute "echo -e "new_passwd\nnew_passwd" | passwd a_user" SyntaxError: (irb):48: syntax error, unexpected tIDENTIFIER, expecting $end rbox.execute "echo -e "new_passwd\nnew_passwd" | passwd a_user" ^ from /Users/riccardotacconi/.rvm/rubies/ruby-1.9.3-preview1/bin/irb:16:in

'

So execute does not like \n

I would like to know how to respond to a server prompt, like send/expect