-----> Installing dependencies with npm 1.0.94

       > libxmljs@0.5.2 install /tmp/build_2tla4epbiliie/node_modules/libxmljs
       > node-waf configure build

       Checking for program g++ or c++          : /usr/bin/g++ 
       Checking for program cpp                 : /usr/bin/cpp 
       Checking for program ar                  : /usr/bin/ar 
       Checking for program ranlib              : /usr/bin/ranlib 
       Checking for g++                         : ok  
       Checking for node path                   : not found 
       Checking for node prefix                 : ok /tmp/node-node-MGI8 
       Checking for program xml2-config         : /usr/bin/xml2-config 
       'configure' finished successfully (0.080s)
       Waf: Entering directory `/tmp/build_2tla4epbiliie/node_modules/libxmljs/build'
       [ 1/10] cxx: src/libxmljs.cc -> build/default/src/libxmljs_1.o
       [ 2/10] cxx: src/xml_attribute.cc -> build/default/src/xml_attribute_1.o
       [ 3/10] cxx: src/xml_document.cc -> build/default/src/xml_document_1.o
       [ 4/10] cxx: src/xml_element.cc -> build/default/src/xml_element_1.o
       [ 5/10] cxx: src/xml_namespace.cc -> build/default/src/xml_namespace_1.o
       [ 6/10] cxx: src/xml_node.cc -> build/default/src/xml_node_1.o
       [ 7/10] cxx: src/xml_sax_parser.cc -> build/default/src/xml_sax_parser_1.o
       [ 8/10] cxx: src/xml_syntax_error.cc -> build/default/src/xml_syntax_error_1.o
       ../src/xml_sax_parser.cc:18: error: 'Persistent' was not declared in this scope
       ../src/xml_sax_parser.cc:18: error: 'String' was not declared in this scope
       ../src/xml_sax_parser.cc:18: error: '::New' has not been declared
       ../src/xml_sax_parser.cc:18: error: 'String' has not been declared
       Waf: Leaving directory `/tmp/build_2tla4epbiliie/node_modules/libxmljs/build'
       Build failed:  -> task failed (err #1): 
        {task: cxx xml_sax_parser.cc -> xml_sax_parser_1.o}
       npm ERR! error installing libxmljs@0.5.2 Error: libxmljs@0.5.2 install: `node-waf configure build`
       npm ERR! error installing libxmljs@0.5.2 `sh "-c" "node-waf configure build"` failed with 1
       npm ERR! error installing libxmljs@0.5.2     at ChildProcess.<anonymous> (/tmp/node-npm-RFUR/lib/utils/exec.js:49:20)
       npm ERR! error installing libxmljs@0.5.2     at ChildProcess.emit (events.js:67:17)
       npm ERR! error installing libxmljs@0.5.2     at ChildProcess.onexit (child_process.js:192:12)

       > libxmljs@0.5.2 preuninstall /tmp/build_2tla4epbiliie/node_modules/libxmljs
       > node-waf clean

       'clean' finished successfully (0.005s)
       npm ERR! libxmljs@0.5.2 install: `node-waf configure build`
       npm ERR! `sh "-c" "node-waf configure build"` failed with 1
       npm ERR! 
       npm ERR! Failed at the libxmljs@0.5.2 install script.
       npm ERR! This is most likely a problem with the libxmljs package,
       npm ERR! not with npm itself.
       npm ERR! Tell the author that this fails on your system:
       npm ERR!     node-waf configure build
       npm ERR! You can get their info via:
       npm ERR!     npm owner ls libxmljs
       npm ERR! There is likely additional logging output above.
       npm ERR! 
       npm ERR! System Linux 2.6.32-341-ec2
       npm ERR! command "/tmp/node-node-MGI8/bin/node" "/tmp/node-npm-RFUR/cli.js" "install"
       npm ERR! cwd /tmp/build_2tla4epbiliie
       npm ERR! node -v v0.4.7
       npm ERR! npm -v 1.0.94
       npm ERR! code ELIFECYCLE
       npm ERR! 
       npm ERR! Additional logging details can be found in:
       npm ERR!     /tmp/build_2tla4epbiliie/npm-debug.log
       npm not ok
 !     Failed to install dependencies with npm
 !     Heroku push rejected, failed to compile Node.js app