Recent jdk sources failed to compile on Ubuntu 7.04 (64bit). Here is extract from the log (attached).

...

../../../build/linux-amd64/tmp/sun/sun.awt/splashscreen/obj64_g/png.o: In function `png_init_mmx_flags':
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/png.c:830: undefined reference to `png_mmx_support'
../../../build/linux-amd64/tmp/sun/sun.awt/splashscreen/obj64_g/pngpread.o: In function `png_push_process_row':
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngpread.c:847: undefined reference to `png_read_filter_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngpread.c:866: undefined reference to `png_do_read_interlace'
../../../build/linux-amd64/tmp/sun/sun.awt/splashscreen/obj64_g/pngpread.o: In function `png_progressive_combine_row':
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngpread.c:1595: undefined reference to `png_combine_row'
../../../build/linux-amd64/tmp/sun/sun.awt/splashscreen/obj64_g/pngread.o: In function `png_read_row':
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:651: undefined reference to `png_combine_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:661: undefined reference to `png_combine_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:671: undefined reference to `png_combine_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:681: undefined reference to `png_combine_row'
../../../build/linux-amd64/tmp/sun/sun.awt/splashscreen/obj64_g/pngread.o:/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:691: more undefined references to `png_combine_row' follow
../../../build/linux-amd64/tmp/sun/sun.awt/splashscreen/obj64_g/pngread.o: In function `png_read_row':
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:774: undefined reference to `png_read_filter_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:804: undefined reference to `png_do_read_interlace'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:807: undefined reference to `png_combine_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:810: undefined reference to `png_combine_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:817: undefined reference to `png_combine_row'
/export/java2d/j2se/make/sun/splashscreen/../../../src/share/native/sun/awt/libpng/pngread.c:819: undefined reference to `png_combine_row'
collect2: ld returned 1 exit status
make[3]: *** [../../../build/linux-amd64/lib/amd64/libsplashscreen.so] Error 1
make[3]: Leaving directory `/export/java2d/j2se/make/sun/splashscreen'
make[2]: *** [all] Error 1
make[2]: Leaving directory `/export/java2d/j2se/make/sun'
make[1]: *** [all] Error 1
make[1]: Leaving directory `/export/java2d/j2se/make'
make: *** [debug] Error 2
Command exited with non-zero status 2