diff --git a/Rakefile b/Rakefile
index a00aa4d..96dae35 100644
--- a/Rakefile
+++ b/Rakefile
@@ -5,14 +5,14 @@ directory "pkg/classes"
 desc "Clean up build artifacts"
 task :clean do
   rm_rf "pkg/classes"
-  rm_rf "lib/cloby_ext.jar"
+  rm_rf "javalib/cloby_ext.jar"
 end
 
 desc "Compile the extension"
 task :compile => "pkg/classes" do |t|
   ant.javac :srcdir => "src", :destdir => t.prerequisites.first,
     :source => "1.5", :target => "1.5", :debug => true,
-    :classpath => "${java.class.path}:${sun.boot.class.path}:lib/clojure-1.2.0.jar"
+    :classpath => "${java.class.path}:${sun.boot.class.path}:javalib/clojure-1.2.0.jar"
 end
 
 desc "Build the jar"
@@ -26,3 +26,11 @@ desc "Run the specs"
 task :spec => :jar do
   ruby "-S", "spec", "spec"
 end
+
+desc "install the jar"
+task :install => :jar do
+  current_ruby = `/bin/bash -l -c 'rvm current'`.strip
+  gem_dir = "/Users/tim/.rvm/gems/#{current_ruby}/gems/cloby-0.0.3-java/lib"
+  puts "copying cloby_ext.jar to #{gem_dir}"
+  `cp javalib/cloby_ext.jar #{gem_dir}`
+end
\ No newline at end of file
diff --git a/src/org/jruby/clojure/ClojureLibrary.java b/src/org/jruby/clojure/ClojureLibrary.java
index 26e48f1..409587d 100644
--- a/src/org/jruby/clojure/ClojureLibrary.java
+++ b/src/org/jruby/clojure/ClojureLibrary.java
@@ -43,11 +43,13 @@ public ClojureObject(Ruby runtime, RubyClass klass) {
 
         @Override
         public Object getVariable(int index) {
+            if (index < 0) return null;
             return ((IPersistentVector)variableTable.deref()).nth(index);
         }
 
         @Override
         public void setVariable(int index, Object value) {
+            if (index < 0) return;
             try {
                 variableTable.set(((IPersistentVector)variableTable.deref()).assocN(index, value));
             } catch (IllegalStateException ise) {