Trouble building gcj 4.8.1

Hi there,

I am trying to compile GCJ 4.8.1 with --enable-java-maintainer-mode
(as classpath has holes in it I need to fix for my codebase to
compile).

Unfortunately this does not work and I'm unsure why. I have ecj.jar in
the source tree.

~/gcc-build$ ../gcc-4.8.1/configure
--prefix=/usr/local/google/home/hearn/gcc-install
--enable-languages=java --disable-bootstrap
--enable-java-maintainer-mode

... results in the classpath configure script failing:

configure:24065: /usr/local/google/home/hearn/gcc-build/./gcc/gcj
-B/usr/local/google/home/hearn/gcc-build/x86_64-unknown-linux-gnu/32/libjava/
-B/usr/local/google/home/hearn/gcc-build/x86_64-unknown-linux-gnu/32/libjava/
-B/usr/local/google/home/hearn/gcc-build/./gcc/
-B/usr/local/google/home/hearn/gcc-install/x86_64-unknown-linux-gnu/bin/
-B/usr/local/google/home/hearn/gcc-install/x86_64-unknown-linux-gnu/lib/
-isystem /usr/local/google/home/hearn/gcc-install/x86_64-unknown-linux-gnu/include
-isystem /usr/local/google/home/hearn/gcc-install/x86_64-unknown-linux-gnu/sys-include
 -m32 -C -g  -fsource=1.5 -ftarget=1.5 Object.java
Unrecognized option :
-fbootclasspath=./:/usr/local/google/home/hearn/gcc-install/share/java/libgcj-4.8.1.jar

Why would GCJ be unable to recognize the -fbootclasspath option?  This
seems an obscure failure.