Rice: ERROR: Failed to build gem native extension

Hello, folks rubyists !
I report there after some error (2) that I encounter. In case someone meet the same or has already met it !
I don't really need a solution so don't bother investigating too much on it !
cheers

config.log (10.4 KB)

gem_make.out (956 Bytes)

···

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  /usr/bin/gem1.9 install rdoc RedCloth rice rspec rubyforge RubyInline

Successfully installed rdoc-2.3.0
Building native extensions. This could take a while...
Successfully installed RedCloth-4.1.1
Building native extensions. This could take a while...
ERROR: Error installing rice:
         ERROR: Failed to build gem native extension.

sh ./configure --prefix=/var/lib/gems/1.9.0/gems/rice-1.0.2/ruby/lib
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking for g++... g++
checking for C++ compiler default output file name... a.out
checking whether the C++ compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C++ compiler... yes
checking whether g++ accepts -g... yes
checking for style of include used by make... GNU
checking dependency style of g++... gcc3
checking for ranlib... ranlib
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
checking for ruby.h... no
configure: error: could not find ruby.h (check config.log)

Gem files will remain installed in /var/lib/gems/1.9.0/gems/rice-1.0.2 for inspection.
Results logged to /var/lib/gems/1.9.0/gems/rice-1.0.2/gem_make.out
Successfully installed rspec-1.1.12
Successfully installed rubyforge-1.0.2
Successfully installed ZenTest-3.11.1
Successfully installed RubyInline-3.8.1
6 gems installed
Installing ri documentation for rdoc-2.3.0...
Installing ri documentation for RubyInline-3.8.1...
Updating ri class cache with 1548 classes...
Installing RDoc documentation for rdoc-2.3.0...
ERROR: While generating documentation for rdoc-2.3.0
... MESSAGE: Error while evaluating /var/lib/gems/1.9.0/gems/rdoc-2.3.0/lib/rdoc/generator/template/darkfish/classpage.rhtml: undefined method `each' for #<String:0xb29b2b4> (at "r\">Namespace</h3>\n\t\t\t\t<ul class=\"link-list\">\n\t\t\t\t\t")
... RDOC args: bin lib History.txt Manifest.txt README.txt RI.txt test/test.ja.txt
(continuing with the rest of the installation)
Installing RDoc documentation for RedCloth-4.1.1...
ERROR: While generating documentation for RedCloth-4.1.1
... MESSAGE: Error while evaluating /var/lib/gems/1.9.0/gems/rdoc-2.3.0/lib/rdoc/generator/template/darkfish/classpage.rhtml: undefined method `each' for #<String:0xb870bf8> (at "r\">Namespace</h3>\n\t\t\t\t<ul class=\"link-list\">\n\t\t\t\t\t")
... RDOC args: lib ext lib/case_sensitive_require CHANGELOG lib/case_sensitive_require/RedCloth.rb lib/redcloth/erb_extension.rb lib/redcloth/formatters/base.rb lib/redcloth/formatters/html.rb lib/redcloth/formatters/latex.rb lib/redcloth/textile_doc.rb lib/redcloth/version.rb lib/redcloth.rb README
(continuing with the rest of the installation)
Installing RDoc documentation for rspec-1.1.12...
ERROR: While generating documentation for rspec-1.1.12
... MESSAGE: Error while evaluating /var/lib/gems/1.9.0/gems/rdoc-2.3.0/lib/rdoc/generator/template/darkfish/classpage.rhtml: undefined method `each' for #<String:0xb621dd4> (at "r\">Namespace</h3>\n\t\t\t\t<ul class=\"link-list\">\n\t\t\t\t\t")
... RDOC args: lib History.txt License.txt Manifest.txt README.txt TODO.txt examples/failing/README.txt examples/passing/priority.txt spec/spec/runner/empty_file.txt spec/spec/runner/examples.txt spec/spec/runner/failed.txt
(continuing with the rest of the installation)
Installing RDoc documentation for rubyforge-1.0.2...
ERROR: While generating documentation for rubyforge-1.0.2
... MESSAGE: Error while evaluating /var/lib/gems/1.9.0/gems/rdoc-2.3.0/lib/rdoc/generator/template/darkfish/classpage.rhtml: undefined method `each' for #<String:0x9ccdd38> (at "r\">Namespace</h3>\n\t\t\t\t<ul class=\"link-list\">\n\t\t\t\t\t")
... RDOC args: lib History.txt Manifest.txt README.txt
(continuing with the rest of the installation)
Installing RDoc documentation for ZenTest-3.11.1...
ERROR: While generating documentation for ZenTest-3.11.1
... MESSAGE: Error while evaluating /var/lib/gems/1.9.0/gems/rdoc-2.3.0/lib/rdoc/generator/template/darkfish/classpage.rhtml: undefined method `each' for #<String:0xc66969c> (at "r\">Namespace</h3>\n\t\t\t\t<ul class=\"link-list\">\n\t\t\t\t\t")
... RDOC args: lib History.txt Manifest.txt README.txt articles/how_to_use_zentest.txt example.txt
(continuing with the rest of the installation)
Installing RDoc documentation for RubyInline-3.8.1...