It may happen that at time while deleting the ruby gem the error can be :
ERROR: While executing gem ... (Gem::InstallError)
Unknown gem rake >= 0
This generally happens when there are multiple gem paths.
type ‘gem env’
RubyGems Environment:
– RUBYGEMS VERSION: 1.6.2
– RUBY VERSION: 1.9.2 (2011-07-09 patchlevel 290) [i386-darwin10.7.1]
– INSTALLATION DIRECTORY: /Users/hrastogi/.rvm/gems/ruby-1.9.2-p290
– RUBY EXECUTABLE: /Users/hrastogi/.rvm/rubies/ruby-1.9.2-p290/bin/ruby
– EXECUTABLE DIRECTORY: /Users/hrastogi/.rvm/gems/ruby-1.9.2-p290/bin
– RUBYGEMS PLATFORMS:
– ruby
– x86-darwin-10
– GEM PATHS:
– /Users/xxxx/.rvm/gems/ruby-1.9.2-p290
– /Users/xxxx/.rvm/gems/ruby-1.9.2-p290@global
– GEM CONFIGURATION:
– :update_sources => true
– :verbose => true
– :benchmark => false
– :backtrace => false
– :bulk_threshold => 1000
– REMOTE SOURCES:
– http://rubygems.org/
Gem is installed in multiple paths. Try deleting manually from one of the path
gem uninstall rake -i /Users/xxxx/.rvm/gems/ruby-1.9.2-p290@global
Tech Read.. 
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Hi Ben, I am tying to do a simple pgorram written in Ruby. Here is what I want to accomplish.1. user input the extension and get that input, assigned it to a variable myvar 2. check to see if myvar is a valid extension.I have created 2 extension on FreePBX (200 and 201), my problem is that I don’t know what variable name is holding the 200 and 201 or Are all the extension that I created on FreePBX goes to a database if so, What is the name of the database and how can I access it. That is why I can’t validate if myvar is a valid extension. Pardon me for bothering you again and I don’t know if I can ask question like this on your blog. Thanks.
This is way better than a brick & mortar establishment.
Interesting article. Scottish Blogs (wot I run) died last month and I want to recsurert it but do it much better! Great ideas in here.And the registering thing is bad, there are a few blogs that I still read but never comment on for precisely that reason.
Wait, I cannot fathom it being so straightforward.
That’s an intelligent answer to a difficult question xxx