diff --git a/eclipse.spec b/eclipse.spec
index b46b1bd..b66448d 100644
--- a/eclipse.spec
+++ b/eclipse.spec
@@ -18,6 +18,11 @@ Epoch:	1
 %else
 %define eclipse_arch   %{_arch}
 %endif
+%ifarch %{ix86} x86_64
+%define native_ecj   1
+%else
+%define native_ecj   0
+%endif
 
 Summary:        %{pkg_summary}
 Name:           eclipse
@@ -38,7 +43,6 @@ Source11:	%{name}-fedora-splash-3.1.2.png
 Source16:       %{name}-copy-platform.sh
 Source17:       %{name}-efj-wrapper.sh
 Source19:       %{name}-filenamepatterns.txt
-Source20:	ecj.sh.in
 Source21:	rebuild-sdk-features
 
 # Build libswt-mozilla and libswt-cairo and use O2
@@ -543,7 +547,6 @@ popd
 
 
 %build
-env
 ORIGCLASSPATH=$CLASSPATH
 
 %if %{gcj_support}
@@ -570,20 +573,25 @@ ORIGCLASSPATH=$CLASSPATH
   # Delete our modified ecj and restore the backup
   rm -rf ecj-bootstrap-tmp
   
+%if %{native_ecj}
   # 1b. Natively-compile it
   gcj -fPIC -fjni -findirect-dispatch -shared -Wl,-Bsymbolic \
     -o ecj-bootstrap.jar.so ecj-bootstrap.jar
    
   gcj-dbtool -n ecj-bootstrap.db 30000
   gcj-dbtool -a ecj-bootstrap.db ecj-bootstrap.jar{,.so}
+%endif
   
   # 2a. Build ecj
   export CLASSPATH=ecj-bootstrap.jar:$ORIGCLASSPATH
+%if %{native_ecj}
   export ANT_OPTS="-Dgnu.gcj.precompiled.db.path=`pwd`/ecj-bootstrap.db"
 %endif
+%endif
 ant -buildfile jdtcoresrc/compilejdtcorewithjavac.xml
 
 %if %{gcj_support}
+%if %{native_ecj}
   # 2b. Natively-compile ecj
   gcj -fPIC -fjni -findirect-dispatch -shared -Wl,-Bsymbolic \
     -o jdtcoresrc/ecj.jar.so jdtcoresrc/ecj.jar
@@ -597,12 +605,14 @@ ant -buildfile jdtcoresrc/compilejdtcorewithjavac.xml
   # To enSURE we're not using any pre-compiled ecj on the build system, set this
   export ANT_OPTS="-Dgnu.gcj.precompiled.db.path=`pwd`/jdtcoresrc/ecj.db"
 %endif
+%endif
 
 # 3. Use this ecj to rebuild itself
 export CLASSPATH=`pwd`/jdtcoresrc/ecj.jar:$ORIGCLASSPATH
 ant -buildfile jdtcoresrc/compilejdtcore.xml
 
 %if %{gcj_support}
+%if %{native_ecj}
   # Natively-compile it
   gcj -fPIC -fjni -findirect-dispatch -shared -Wl,-Bsymbolic \
     -o ecj.jar.so ecj.jar
@@ -613,6 +623,7 @@ ant -buildfile jdtcoresrc/compilejdtcore.xml
   # Remove old native bits
   rm jdtcoresrc/ecj.db jdtcoresrc/ecj.jar.so
 %endif
+%endif
 
 # Build the rest of Eclipse
 export CLASSPATH=`pwd`/ecj.jar:$ORIGCLASSPATH
@@ -651,6 +662,8 @@ tar -C $RPM_BUILD_ROOT%{_datadir} -zxf \
   result/linux-gtk-%{eclipse_arch}-sdk.tar.gz
 
 pushd $RPM_BUILD_ROOT%{_datadir}/%{name}
+# extract jdtCompilerAdapter.jar from org.eclipse.jdt.core_3.1.2.jar
+unzip -d plugins plugins/org.eclipse.jdt.core_3.1.2.jar jdtCompilerAdapter.jar
 
 # Extract .so files
 # https://bugs.eclipse.org/bugs/show_bug.cgi?id=90535
@@ -908,13 +921,18 @@ mkdir -p $RPM_BUILD_ROOT%{_datadir}/java
 ln -s %{_datadir}/%{name}/plugins/org.eclipse.jdt.core_%{eclipse_majmin}.%{eclipse_micro}.jar \
   $RPM_BUILD_ROOT%{_datadir}/java/eclipse-ecj.jar
 
-# Install /usr/bin/ecj script
-sed 's:@JAVADIR@:%{_javadir}:g' < %{SOURCE20} > ecj
-install -m755 ecj $RPM_BUILD_ROOT%{_bindir}
-rm ecj
-
 %if %{gcj_support}
 aot-compile-rpm
+
+# Build and install ecj binary
+pushd $RPM_BUILD_ROOT%{_libdir}/gcj/%{name}
+  gcj -g -O2 --main=org.eclipse.jdt.internal.compiler.batch.Main \
+    -Wl,-R,%{_libdir}/gcj/%{name} \
+    org.eclipse.jdt.core_3.1.2.jar.so jdtCompilerAdapter.jar.so -o \
+    $RPM_BUILD_ROOT%{_bindir}/ecj
+popd
+chmod a+x $RPM_BUILD_ROOT%{_bindir}/ecj
+
 %endif
 
 %clean
@@ -1041,12 +1059,15 @@ fi
 %dir %{_datadir}/%{name}/features
 %dir %{_datadir}/%{name}/configuration
 %{_datadir}/%{name}/plugins/org.eclipse.jdt.core_3.*
+%{_datadir}/%{name}/plugins/jdtCompilerAdapter.jar
 %{_datadir}/java/eclipse-ecj.jar
 %if %{gcj_support}
 # Native bits
 %dir %{_libdir}/gcj/%{name}
 %{_libdir}/gcj/%{name}/org.eclipse.jdt.core_3.1.2.jar.so
 %{_libdir}/gcj/%{name}/org.eclipse.jdt.core_3.1.2.jar.db
+%{_libdir}/gcj/%{name}/jdtCompilerAdapter.jar.so
+%{_libdir}/gcj/%{name}/jdtCompilerAdapter.jar.db
 %{_bindir}/ecj
 %endif
 
@@ -1278,6 +1299,12 @@ fi
 %{_datadir}/%{name}/plugins/org.eclipse.platform.source.linux.gtk.*_%{version}
 
 %changelog
+* Fri Mar 03 2006 Andrew Overholt <overholt@redhat.com> 3.1.2-1jpp_12fc
+- Only build with a native ecj on x86{,_64}
+- Make /usr/bin/ecj native again as it's slow as a script with gij and
+  the chances of a someone using a proprietary JDK and not seeing their
+  javac alternative are slim.
+
 * Tue Feb 28 2006 Andrew Overholt <overholt@redhat.com> 3.1.2-1jpp_12fc
 - Update to tomcat 5.5 (e.o#98371).
 - Don't build on ppc64 until we get the tomcat situation straightened out.