I am also newbies for rails too.
I found an information athttp://www.unwin.org/ruby_on_rails/tips/xml_simple_already_initialize…
But this is not solve my problem too.
I tried to uninstall flickr but it also not solve.
I found the problem on my system to be slightly different than the one
described in the link. The
conflict was due to xmlsimple.rb being included as well as lib/
xmlsimple.rb which is nothing more
than a link to the original file.
The following script worked for me:
if [ -h lib/xmlsimple.rb ]
mv lib/xmlsimple.rb lib/xmlsimple.rb.old
mv xmlsimple.rb lib/.
cat > xmlsimple.rb <<!
echo pwd/lib/xmlsimple.rb is not a link. Exiting.