How to solve BigDecimal 'already initialized persistent' warnings on 'mailcatcher' cmd?

Every time I start mailcatcher I show warnings with constants already initialized. Can anyone advise on how to solve the problem? Thank you. Update below.

/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::BASE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::EXCEPTION_ALL
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::EXCEPTION_NaN
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::EXCEPTION_INFINITY
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::EXCEPTION_UNDERFLOW
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::EXCEPTION_OVERFLOW
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::EXCEPTION_ZERODIVIDE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_MODE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_UP
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_DOWN
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_HALF_UP
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_HALF_DOWN
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_CEILING
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_FLOOR
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::ROUND_HALF_EVEN
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_NaN
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_POSITIVE_ZERO
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_NEGATIVE_ZERO
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_POSITIVE_FINITE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_NEGATIVE_FINITE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_POSITIVE_INFINITE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::SIGN_NEGATIVE_INFINITE
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::INFINITY
/Users/james/.rvm/gems/ruby-2.1.5/extensions/x86_64-darwin-13/2.1.0/bigdecimal-1.2.7/bigdecimal.bundle: warning: already initialized constant BigDecimal::NAN

      

        
        
        
      

    

Update: I have uninstalled gem bigdecimal

and installed gem bigdecimal

, no changes. Then I pointed out gem 'bigdecimal', ~> 1.1

, but no change. Not much when looking for this error. I am running Ruby 2.1.5 and Rails 4.2.1.