Error while updating RubyGems

I got the following error message when I tried to update all my
RubyGems on OS X Tiger (please notice that I did log as ‘root’ prior
to this):

Raven:/Users/untz root# gem update all --include-dependencies
Updating installed gems…
Bulk updating Gem source index for:
Attempting remote update of all
ERROR: While executing gem … (Gem::GemNotFoundException)
Could not find all (> 0) in the repository
Raven:/Users/untz root# gem update --include-dependencies
Updating installed gems…
Attempting remote update of actionmailer
Successfully installed actionmailer-1.3.3
Successfully installed actionpack-1.13.3
Successfully installed activesupport-1.4.2
Installing ri documentation for actionmailer-1.3.3…
Installing ri documentation for actionpack-1.13.3…

RDoc failure in lib/action_controller/cgi_ext/raw_post_data_fix.rb at
or around line 36 column 22

Before reporting this, could you check that the file
you’re documenting compiles cleanly–RDoc is not a
full Ruby parser, and gets confused easily if fed
invalid programs.

The internal error was:

ERROR: While executing gem … (NoMethodError)
undefined method `match_io’ for -517611318:Fixnum

Any help is greatly appreciated!