Building on openSUSE 11.0 Alpha2 (as well as Alpha1) I have been seeing
the following with a plain ./configure --prefix=... (omitting those dozen
fancy options that the distros usually employ).

libtool: compile:  /tmp/OBJ-0219-2155/./gcc/xgcc -shared-libgcc -B/tmp/OBJ-0219-2155/./gcc -nostdinc++ -L/tmp/OBJ-0219-2155/x86_64-unknown-linux-gnu/32/libstdc++-v3/src -L/tmp/OBJ-0219-2155/x86_64-unknown-linux-gnu/32/libstdc++-v3/src/.libs -B/suse/gp/gcc-x86_64/x86_64-unknown-linux-gnu/bin/ -B/suse/gp/gcc-x86_64/x86_64-unknown-linux-gnu/lib/ -isystem /suse/gp/gcc-x86_64/x86_64-unknown-linux-gnu/include -isystem /suse/gp/gcc-x86_64/x86_64-unknown-linux-gnu/sys-include -m32 -DHAVE_CONFIG_H -I. -I/mounts/users-space/gp/gcc/trunk/libjava -I./include -I./gcj -I/mounts/users-space/gp/gcc/trunk/libjava -Iinclude -I/mounts/users-space/gp/gcc/trunk/libjava/include -I/mounts/users-space/gp/gcc/trunk/libjava/classpath/include -Iclasspath/include -I/mounts/users-space/gp/gcc/trunk/libjava/classpath/native/fdlibm -I/mounts/users-space/gp/gcc/trunk/libjava/../boehm-gc/include -I../boehm-gc/include -I/mounts/users-space/gp/gcc/trunk/libjava/libltdl -I/mounts/users-space/gp/gcc/trunk/libjava/libltdl -I/mounts/users-space/gp/gcc/trunk/libjava/.././libjava/../gcc -I/mounts/users-space/gp/gcc/trunk/libjava/../zlib -I/mounts/users-space/gp/gcc/trunk/libjava/../libffi/include -I../libffi/include -fno-rtti -fnon-call-exceptions -fdollars-in-identifiers -Wswitch-enum -D_FILE_OFFSET_BITS=64 -ffloat-store -fomit-frame-pointer -Wextra -Wall -D_GNU_SOURCE -DPREFIX=\"/suse/gp/gcc-x86_64\" -DTOOLEXECLIBDIR=\"/suse/gp/gcc-x86_64/lib/../lib\" -DJAVA_HOME=\"/suse/gp/gcc-x86_64\" -DBOOT_CLASS_PATH=\"/suse/gp/gcc-x86_64/share/java/libgcj-4.4.0.jar\" -DJAVA_EXT_DIRS=\"/suse/gp/gcc-x86_64/share/java/ext\" -DGCJ_ENDORSED_DIRS=\"/suse/gp/gcc-x86_64/share/java/gcj-endorsed\" -DGCJ_VERSIONED_LIBDIR=\"/suse/gp/gcc-x86_64/lib/../lib/gcj-4.4.0-9\" -DPATH_SEPARATOR=\":\" -DECJ_JAR_FILE=\"\" -DLIBGCJ_DEFAULT_DATABASE=\"/suse/gp/gcc-x86_64/lib/../lib/gcj-4.4.0-9/classmap.db\" -DLIBGCJ_DEFAULT_DATABASE_PATH_TAIL=\"gcj-4.4.0/classmap.db\" -g -O2 -D_GNU_SOURCE -m32 -MT posix-threads.lo -MD -MP -MF .deps/posix-threads.Tpo -c /mounts/users-space/gp/gcc/trunk/libjava/posix-threads.cc -o posix-threads.o >/dev/null 2>&1
here=`pwd`; cd /mounts/users-space/gp/gcc/trunk/libjava/classpath/lib; \
        find gnu java javax org sun -name .svn -prune -o -name '*.class' -print | \
        gjar -cfM@ $here/libgcj-4.4.0.jar
jar: internal error:
java.lang.NullPointerException: man
        at java.util.jar.JarOutputStream.<init>(JarOutputStream.java:43)
        at  gnu.classpath.tools.jar.Creator.writeCommandLineEntries(Creator.java:225)
        at gnu.classpath.tools.jar.Creator.run(Creator.java:246)
        at gnu.classpath.tools.jar.Main.run(Main.java:276)
        at gnu.classpath.tools.jar.Main.main(Main.java:284)
gmake[5]: *** [libgcj-4.4.0.jar] Error 1
gmake[5]: Leaving directory `/tmp/OBJ-0219-2155/x86_64-unknown-linux-gnu/32/libjava'
gmake[4]: *** [all-recursive] Error 1
gmake[4]: Leaving directory `/tmp/OBJ-0219-2155/x86_64-unknown-linux-gnu/32/libjava'
gmake[3]: *** [multi-do] Error 1
gmake[3]: Leaving directory `/tmp/OBJ-0219-2155/x86_64-unknown-linux-gnu/libjava'
gmake[2]: *** [all-multi] Error 2
gmake[2]: Leaving directory `/tmp/OBJ-0219-2155/x86_64-unknown-linux-gnu/libjava'
gmake[1]: *** [all-target-libjava] Error 2
gmake[1]: Leaving directory `/tmp/OBJ-0219-2155'
gmake: *** [bootstrap-lean] Error 2