Invalid gemspec because of the date format in specification

I faced this issue several times, and it appeared again yesterday. Here are the solution for this error. Invalid gemspec in [/opt/ruby/lib/ruby/gems/1.8/specifications/uniform_notifier-1.0.2.gemspec]: Illformed requirement [“# 3.0”] Invalid gemspec in [/opt/ruby/lib/ruby/gems/1.8/specifications/uniform_notifier-1.0.2.gemspec]: Illformed requirement [“# 3.0”]
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