Oauth consumer and provider gives signature_invalid error

hi All, I'm trying develop Oauth consumer and provider as very same way of twitter. I followed the below tutorials. Here is my consumer code http://pastebin.com/39sxKbuz and here is my provider code http://pastebin.com/xtEsrTGf when I run the client it gives error as follow Array ( [oauth_problem] => signature_invalid [debug_sbs] => GET [http%253A%252F%252Fwww.abc.loc%252Foauth%252Frequesttoken] => [oauth_consumer_key%253D1d7259a770e0732d191bb566b5cf9e%2526oauth_nonce%253Db4168962db5559eb55859f1699622d07%2526oauth_signature_method%253DHMAC-SHA1%2526oauth_timestamp%253D1317621581%2526oauth_version%253D1.0%2526route%253Doauth%25252Frequesttoken] => ) may be I'm doing this in a wrong way or not understood properly so your suggestions are welcome. And I really appreciate if someone can explain what are the wrong codes here and how I correct them. thanks a bunch . ~Chamila Gayan