rubygems.rb:550:in `initialize': not in gzip format (Zlib::GzipFile::Error)

rubygems.rb:550:in `initialize': not in gzip format (Zlib::GzipFile::Error)

when i try to run the command 'bundle install' or installing particular
gem then ot in gzip format (Zlib::GzipFile::Error) occurs. i have done
googling and find some of the answers like removing cache ,bundle packages
but all fail in my case
i am using rails 3.2.11 and ruby 1.8.7
the code of rubygems line arround 500 is
def self.gunzip(data) require 'stringio' require 'zlib' data =
StringIO.new data
Zlib::GzipReader.new(data).read
end
## # Zlib::GzipWriter wrapper that zips +data+.
def self.gzip(data) require 'stringio' require 'zlib' zipped = StringIO.new
Zlib::GzipWriter.wrap zipped do |io| io.write data end
zipped.string
end
while error in console is
Unfortunately, a fatal error has occurred. Please see the Bundler
troubleshooting documentation at http://bit.ly/bundler-issues. Thanks!
/usr/lib/ruby/site_ruby/1.8/rubygems.rb:550:in `initialize': not in gzip
format (Zlib::GzipFile::Error)
from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:550:in `new'
from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:550:in `gunzip'
from /usr/lib/ruby/site_ruby/1.8/rubygems/remote_fetcher.rb:177:in
`fetch_path'
from /usr/lib/ruby/site_ruby/1.8/rubygems/spec_fetcher.rb:270:in
`load_specs'
from /usr/lib/ruby/site_ruby/1.8/rubygems/spec_fetcher.rb:243:in `list'
from /usr/lib/ruby/site_ruby/1.8/rubygems/spec_fetcher.rb:239:in `each'
from /usr/lib/ruby/site_ruby/1.8/rubygems/spec_fetcher.rb:239:in `list'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/rubygems_integration.rb:104:in
`fetch_specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/rubygems_integration.rb:117:in
`fetch_all_remote_specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/fetcher.rb:262:in
`fetch_all_remote_specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/fetcher.rb:116:in
`specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/source/rubygems.rb:235:in
`remote_specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/source/rubygems.rb:235:in
`each'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/source/rubygems.rb:235:in
`remote_specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/source/rubygems.rb:163:in
`fetch_specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/source/rubygems.rb:67:in
`specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:192:in
`index'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:189:in
`each'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:189:in
`index'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/index.rb:9:in
`build'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:185:in
`index'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:179:in
`resolve'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:114:in
`specs'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/definition.rb:109:in
`resolve_remotely!'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/installer.rb:83:in
`run'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/installer.rb:14:in
`install'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/cli.rb:320:in
`update'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/vendor/thor/task.rb:27:in
`__send__'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/vendor/thor/task.rb:27:in
`run'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/vendor/thor/invocation.rb:120:in
`invoke_task'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/vendor/thor.rb:344:in
`dispatch'
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/vendor/thor/base.rb:434:in
`start'
from /usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/bin/bundle:20
from
/usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/lib/bundler/friendly_errors.rb:3:in
`with_friendly_errors'
from /usr/lib64/ruby/gems/1.8/gems/bundler-1.3.5/bin/bundle:20
from /usr/bin/bundle:19:in `load'
from /usr/bin/bundle:19
Hope this information will be enough for providing me the right way for
solution