re-write for less variables
diff --git a/releng.wtpbuilder/distribution/wtp.site/build.xml b/releng.wtpbuilder/distribution/wtp.site/build.xml
index 03cf736..857e8e9 100644
--- a/releng.wtpbuilder/distribution/wtp.site/build.xml
+++ b/releng.wtpbuilder/distribution/wtp.site/build.xml
@@ -1,9 +1,17 @@
 <project name="Build specific targets and properties" default="build">
+
+    <!-- Note to be cross-platform, "environment variables" are only appropriate for
+        some variables, e.g. ones we set, since properties are case sensitive, even if
+        the environment variables on your operating system are not, e.g. it will
+        be ${env.Path} not ${env.PATH} on Windows -->
+    <property environment="env" />
+
+
     <target name="build">
         <java classpath="${pde.builder.path}/startup.jar" fork="true" classname="org.eclipse.core.launcher.Main" failonerror="true">
-            <jvmarg value="-Dosgi.ws=${basews}" />
-            <jvmarg value="-Dosgi.os=${baseos}" />
-            <jvmarg value="-Dosgi.arch=${basearch}" />
+            <jvmarg value="-Dosgi.ws=${env.BASEWS}" />
+            <jvmarg value="-Dosgi.os=${env.BASEOS}" />
+            <jvmarg value="-Dosgi.arch=${env.BASEARCH}" />
             <jvmarg value="-Dbuild.home=${build.home}" />
             <jvmarg value="-Dbuild.trial=${build.trial}" />
             <jvmarg value="-DbuildBranch=${buildBranch}" />
@@ -51,7 +59,7 @@
             <property name="webtoolsDownloadURL" value="http://www.eclipse.org/downloads/download.php?file=/webtools/committers/drops"/>
 
             <property name="buildBranch" value="${buildBranch}" />
-        	<property name="build.pack-all-in-one" value="${build.pack-all-in-one}"/>
+            <property name="build.pack-all-in-one" value="${build.pack-all-in-one}"/>
 
             <property name="isBuildTested" value="${isBuildTested}" />
             <property name="indexTemplateFilename" value="${indexTemplateFilename}" />