server problem or rails problem?

Hello,
im trying to upload my rails app to an shared hosting environment.
The application works fine on my development machine ( as it usually
does ).
but after uploading it running bundle install and then mogrel I still
get a dependency error:

activesupport-3.0.0/lib/active_support/dependencies.rb:239:in
`require': no such file to load -- dispatcher (LoadError)
  from /home/gregory/ruby/gems/gems/activesupport-3.0.0/lib/
active_support/dependencies.rb:239:in `require'
  from /home/gregory/ruby/gems/gems/activesupport-3.0.0/lib/
active_support/dependencies.rb:227:in `load_dependency'
  from /home/gregory/ruby/gems/gems/activesupport-3.0.0/lib/
active_support/dependencies.rb:239:in `require'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/../lib/mongrel/
rails.rb:148:in `rails'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/mongrel_rails:
113:in `cloaker_'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/../lib/mongrel/
configurator.rb:149:in `call'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/../lib/mongrel/
configurator.rb:149:in `listener'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/mongrel_rails:
99:in `cloaker_'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/../lib/mongrel/
configurator.rb:50:in `call'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/../lib/mongrel/
configurator.rb:50:in `initialize'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/mongrel_rails:
84:in `new'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/mongrel_rails:
84:in `run'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/../lib/mongrel/
command.rb:212:in `run'
  from /usr/lib/ruby/gems/1.8/gems/mongrel-1.1.5/bin/mongrel_rails:281
  from /usr/bin/mongrel_rails:19:in `load'
  from /usr/bin/mongrel_rails:19

is this a problem with the server or is something wrong with the
application?

( searching on Google found nothing )

thanks for any help, Adam