How can I use PLAINTEXT signature?

[Chris Varenhorst]

Can't seem to find much documentation on this. It seems when I
set :signature_method the only option that works is "HMAC-SHA1".
Anything else I want (plaintext) and I get an
OAuth::Signature::UnknownSignatureMethod.

Here's some example code..

@oauth_conf = {
:site => "https://" + API_SERVER,
:scheme => :header,
:http_method => :post,
:request_token_url => "/#{API_VERSION}/oauth/
request_token",
:access_token_url => "/#{API_VERSION}/oauth/access_token",
:authorize_url => "/#{API_VERSION}/oauth/authorize",
:signature_method => "plaintext",
}

@consumer = OAuth::Consumer.new(@consumer_key,
@consumer_secret, @oauth_conf)

here's the stack trace..

gems/oauth-0.4.5/lib/oauth/signature.rb:17:in `build': plaintext
(OAuth::Signature::UnknownSignatureMethod)
gems/oauth-0.4.5/lib/oauth/signature.rb:40:in
`body_hash'
gems/ruby-1.9.2-p180/gems/oauth-0.4.5/lib/oauth/client/helper.rb:60:in
`hash_body'
gems/oauth-0.4.5/lib/oauth/client/net_http.rb:29:in
`oauth!'
gems/ruby-1.9.2-p180/gems/oauth-0.4.5/lib/oauth/consumer.rb:227:in
`sign!'
gems/ruby-1.9.2-p180/gems/oauth-0.4.5/lib/oauth/consumer.rb:191:in
`create_signed_request'
gems/oauth-0.4.5/lib/oauth/consumer.rb:162:in
`request'
gems/ruby-1.9.2-p180/gems/oauth-0.4.5/lib/oauth/consumer.rb:197:in
`token_request'
gems/ruby-1.9.2-p180/gems/oauth-0.4.5/lib/oauth/consumer.rb:139:in
`get_request_token'
lib/api_sdk.rb:41:in `get_request_token


any ideas?