Please take a look at log:
/java/re/jdk/1.3.1-update/nightly/logs/build-solaris-sparc.log

..
..
..
/../build/solaris-sparc/tmp/sun/java.net/net/obj/net_util.d
/localtools/solaris-sparc/SC5.0/bin/cc -Xa -xO2 -xcg92 -Wc,-Qrm-s -Wc,-Qiselect-T0 -v -xtemp=../../../build/solaris-sparc/tmp/sun/java.net/net/obj -L../../../build/solaris-sparc/tmp/sun/java.net/net/obj -xstrconst -erroff=E_NON_CONST_INIT -KPIC -DTRIMMED -DMACRO_MEMSYS_OPS -DBREAKPTS -DTRACING -Dsparc -DSOLARIS2 -D__solaris__ -D_REENTRANT -I. -I../../../build/solaris-sparc/tmp/sun/java.net/net/CClassHeaders -I../../../src/solaris/javavm/export -I../../../src/share/javavm/export -I../../../src/share/native/common -I../../../src/solaris/native/common -I../../../src/share/native/java/net -I../../../src/solaris/native/java/net -c -o ../../../build/solaris-sparc/tmp/sun/java.net/net/obj/net_util_md.o ../../../src/solaris/native/java/net/net_util_md.c
"../../../src/solaris/native/java/net/net_util_md.c", line 47gnumake[3]: Leaving directory `/export/sail3/jdk131-update/ws/nb/jdk/make/java/net'
: syntax error before or at: /
cc: acomp failed for ../../../src/solaris/native/java/net/net_util_md.c
gnumake[3]: *** [../../../build/solaris-sparc/tmp/sun/java.net/net/obj/net_util_md.o] Error 2
gnumake[2]: *** [optimized] Error 2
gnumake[1]: *** [all] Error 1
gnumake: *** [all] Error 1
gnumake[2]: Leaving directory `/export/sail3/jdk131-update/ws/nb/jdk/mak