Error while opening SSH

I am new to ruby. I was planning to automate some deployment processes
and ruby scripts seem to provide an excellent medium to achieve the
same. I am trying to start an SSH session and I get following error
shown below. I tried the solution provided at
http://www.mail-archive.com/[email protected]/msg01108.html. I
added the NI_NUMERICSERV flag while getting the IP address in session.rb
file as suggested in the post. But am still gettting the error. Am I
missing anything here?

Thanks
Mahesh

C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/net/ssh/host-
key-verifier.rb:64:in add_key': undefined method mkdir’ for File:Class
(NoMeth
odError)
from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-
ssh-1.1.0/lib/
net/ssh/host-key-verifier.rb:25:in verify' from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/ net/ssh/lenient-host-key-verifier.rb:9:in verify’
from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-
ssh-1.1.0/lib/
net/ssh/transport/kex/dh.rb:165:in verify_server_key' from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/ net/ssh/transport/kex/dh.rb:232:in exchange_keys’
from
C:/development_tools/ruby/lib/ruby/gems/1.8/gems/needle-1.3.0/lib/n
eedle/lifecycle/proxy.rb:60:in __send__' from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/needle-1.3.0/lib/n eedle/lifecycle/proxy.rb:60:in method_missing’
from
C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/
net/ssh/transport/session.rb:183:in exchange_keys' from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0 /lib/ net/ssh/transport/session.rb:144:in kexinit’
… 31 levels…
from
C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/
net/ssh/session.rb:106:in initialize' from C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/ net/ssh.rb:47:in new’
from
C:/development_tools/ruby/lib/ruby/gems/1.8/gems/net-ssh-1.1.0/lib/
net/ssh.rb:47:in `start’
from testssh.rb:3