How to remove password from pdf in mac?

In mac OS, how do you remove a password from a pdf file that is protected by it.
Update: Let me rephrase the question, I know the password of this file, but I want to share this document with others - Effectively want to remove the password from the file and share it as a plain pdf without encryption/password protection.
Update 2: Found the answer after a lot of probing, without having to use any thirdparty software..In Mac OS X Lion open the pdf using "Preview". It'll prompt for password, provide the password, once the pdf opens... Choose "Save a copy", this dialog has options to disable password/encryption and save it.
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