wsdl2ruby help: uninitialized constant SOAP::Mapping::Encode

[Tom Tom]

hi, just created this client with wsdl2ruby (via gem). now running the
client gives me this:

C:\Ruby\00_Apps\1Client>ruby CrmServiceClient.rb
/defaultMappingRegistry.rb:10: uninitialized constant
SOAP::Mapping::EncodedRegistry (NameError)
from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in
`gem_original_require'
from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in
`require'
from ./defaultDriver.rb:2
from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in
`gem_original_require'
from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in
`require'
from CrmServiceClient.rb:2


what am i missing?
thx