Obj_free() called for broken object?

Hi all,

I got past this by simply restarting the process, but can anybody here
tell me
wtf happened here? My Google-fu appears weak today:

ttyp2 [email protected]:/root
1 14:51:49 644 # gem update -y
Updating installed gems…
Need to update 50 gems from http://gems.rubyforge.org

complete
Attempting remote update of gen
Successfully installed gen-0.31.0
Successfully installed glue-0.31.0
Successfully installed facets-1.4.5
Installing ri documentation for gen-0.31.0…
Installing ri documentation for glue-0.31.0…
Installing ri documentation for facets-1.4.5…
Installing RDoc documentation for gen-0.31.0…
Installing RDoc documentation for glue-0.31.0…
Installing RDoc documentation for facets-1.4.5…
Attempting remote update of glue
Successfully installed glue-0.31.0
Installing ri documentation for glue-0.31.0…
/usr/local/lib/ruby/1.8/rdoc/parsers/parse_rb.rb:374: [BUG] obj_free()
called
for broken object
ruby 1.8.4 (2005-12-24) [i386-freebsd6]

Abort trap: 6 (core dumped)