Lately (even before version 101 string fix ) I noticed occasional failures for windows-i586 builds for jdk6.
It is always failed in ishield part.
I start collecting failed logs for feather investigation and this is what I have:

http://jre.us.oracle.com/net/rehudson/n/tiger/jdk6u95/logs/build-windows-i586.log_failed1

Building Release: iftw

ISDEV : fatal error -1014: Cannot rename directory C:\BUILD_AREA\jdk6_95\control\build\windows-i586\tmp\ishield\patch\jre\jre\iftw to C:\BUILD_AREA\jdk6_95\control\build\windows-i586\tmp\ishield\patch\jre\jre\iftw.Bak.
Windows Explorer or a DOS prompt may be pointing to a subfolder of the release output folder (Disk1) or to the Interm folder, locking it. Change the current directory. Close any open files in the Disk1 folder. Close Msidb.exe if it is open.
jre\iftw - 1 error(s), 0 warning(s)

Build finished at Feb 1 2015 03:53 AM
gnumake[7]: *** [create_static_bundle] Error 1
gnumake[7]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[6]: *** [create_bundle] Error 2
gnumake[6]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[5]: *** [all] Error 1
gnumake[5]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield'
gnumake[4]: *** [all] Error 1
gnumake[4]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows'
gnumake[3]: *** [all] Error 2
gnumake[3]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles'
gnumake[2]: *** [all] Error 1
gnumake[2]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer'
gnumake[1]: *** [all] Error 1
gnumake[1]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make'
gnumake: *** [install-build] Error 2
## Windows IA 32-bit local build finished on sc11137317

http://jre.us.oracle.com/net/rehudson/n/tiger/jdk6u95/logs/build-windows-i586.log_failed2

Language Korean built
ISDEV : fatal error -4092: Error opening MSI database C:\BUILD_AREA\jdk6_95\control\build\windows-i586\tmp\ishield\patch\jre\jre\iftw\DiskImages\DISK1\1046.msi
jre\iftw - 1 error(s), 1 warning(s)

Build finished at Feb 1 2015 11:35 AM
gnumake[7]: *** [create_consumer_bundle] Error 1
gnumake[7]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[6]: *** [create_bundle] Error 2
gnumake[6]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[5]: *** [all] Error 1
gnumake[5]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield'
gnumake[4]: *** [all] Error 1
gnumake[4]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows'
gnumake[3]: *** [all] Error 2
gnumake[3]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles'
gnumake[2]: *** [all] Error 1
gnumake[2]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer'
gnumake[1]: *** [all] Error 1
gnumake[1]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make'
gnumake: *** [install-build] Error 2
## Windows IA 32-bit local build finished on sc11137314

http://jre.us.oracle.com/net/rehudson/n/tiger/jdk6u95/logs/build-windows-i586.log_failed3

C:/mksnt/mksnt/cp -f C:/BUILD_~1/jdk6_95/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/iftw/DiskImages/Disk1//*.msi C:/BUILD_~1/jdk6_95/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//1041.msi
cp: target "C:/BUILD_~1/jdk6_95/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//1041.msi" must exist
Usage: cp [-acfimpPqrRSv] file1 [file2 ...] target
gnumake[7]: *** [javaone_transforms] Error 2
gnumake[7]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[6]: *** [create_bundle] Error 2
gnumake[6]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[5]: *** [all] Error 1
gnumake[5]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield'
gnumake[4]: *** [all] Error 1
gnumake[4]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows'
gnumake[3]: *** [all] Error 2
gnumake[3]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles'
gnumake[2]: *** [all] Error 1
gnumake[2]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer'
gnumake[1]: *** [all] Error 1
gnumake[1]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make'
gnumake: *** [install-build] Error 2
## Windows IA 32-bit local build finished on sc11137317


http://jre.us.oracle.com/net/rehudson/n/tiger/jdk6u95/logs/build-windows-i586.log

C:/mksnt/mksnt/cp -f C:/BUILD_~1/jdk6_95/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/iftw/DiskImages/Disk1//*.msi C:/BUILD_~1/jdk6_95/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//2052.msi
cp: target "C:/BUILD_~1/jdk6_95/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//2052.msi" must exist
Usage: cp [-acfimpPqrRSv] file1 [file2 ...] target
gnumake[7]: *** [javaone_transforms] Error 2
gnumake[7]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[6]: *** [create_bundle] Error 2
gnumake[6]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield/jre'
gnumake[5]: *** [all] Error 1
gnumake[5]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows/ishield'
gnumake[4]: *** [all] Error 1
gnumake[4]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles/windows'
gnumake[3]: *** [all] Error 2
gnumake[3]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer/bundles'
gnumake[2]: *** [all] Error 1
gnumake[2]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make/installer'
gnumake[1]: *** [all] Error 1
gnumake[1]: Leaving directory `C:/BUILD_AREA/jdk6_95/install/make'
gnumake: *** [install-build] Error 2
## Windows IA 32-bit local build finished on sc11137317

And the latest one today:

http://jre.us.oracle.com//net/scanas411.us.oracle.com/export/java-re/PRODUCTION/legacy/n/mustang/jdk6_101/logs/build-windows-i586.log_failed3

DoneC:/mksnt/mksnt/cp -f C:/BUILD_~1/jdk6_101/install/make/INSTAL~1/bundles/windows/ishield/jre/../javaad1053.ibd C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/javaad.ibd
C:/Progra~1/Installshield/StandaloneBuild8SP2/IsSaBld.exe -s -p C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre.ism -r "iftw" -c COMP
gnumake[7]: [javaone_transforms] Error 1 (ignored)
C:/mksnt/mksnt/cp -f C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/iftw/DiskImages/Disk1//*.msi C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//1053.msi
cp: target "C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//1053.msi" must exist
Usage: cp [-acfimpPqrRSv] file1 [file2 ...] target
gnumake[7]: *** [javaone_transforms] Error 2
gnumake[7]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows/ishield/jre'
gnumake[6]: *** [create_bundle] Error 2
gnumake[6]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows/ishield/jre'
gnumake[5]: *** [all] Error 1
gnumake[5]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows/ishield'
gnumake[4]: *** [all] Error 1
gnumake[4]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows'
gnumake[3]: *** [all] Error 2
gnumake[3]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles'
gnumake[2]: *** [all] Error 1
gnumake[2]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer'
gnumake[1]: *** [all] Error 1
gnumake[1]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make'
gnumake: *** [install-build] Error 2
## Windows IA 32-bit local build finished on sc11137314

#### ifarmTAG "End Core Build" "" "1426244184"

#### RETAG "End Core Build" "FAILED" "03/13/15 03:56:24"

One more here:
http://jre.us.oracle.com/net/rehudson/n/tiger/jdk6u101/logs/build-windows-i586.log_failed

DoneC:/mksnt/mksnt/cp -f C:/BUILD_~1/jdk6_101/install/make/INSTAL~1/bundles/windows/ishield/jre/../javaad1036.ibd C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/javaad.ibd
C:/Progra~1/Installshield/StandaloneBuild8SP2/IsSaBld.exe -s -p C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre.ism -r "iftw" -c COMP
gnumake[7]: [javaone_transforms] Error 1 (ignored)
C:/mksnt/mksnt/cp -f C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/iftw/DiskImages/Disk1//*.msi C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//1036.msi
cp: target "C:/BUILD_~1/jdk6_101/control/build/WINDOW~1/tmp/ishield/patch/jre/jre/transform/javaone//1036.msi" must exist
Usage: cp [-acfimpPqrRSv] file1 [file2 ...] target
gnumake[7]: *** [javaone_transforms] Error 2
gnumake[7]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows/ishield/jre'
gnumake[6]: *** [create_bundle] Error 2
gnumake[6]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows/ishield/jre'
gnumake[5]: *** [all] Error 1
gnumake[5]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows/ishield'
gnumake[4]: *** [all] Error 1
gnumake[4]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles/windows'
gnumake[3]: *** [all] Error 2
gnumake[3]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer/bundles'
gnumake[2]: *** [all] Error 1
gnumake[2]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make/installer'
gnumake[1]: *** [all] Error 1
gnumake[1]: Leaving directory `C:/BUILD_AREA/jdk6_101/install/make'
gnumake: *** [install-build] Error 2
## Windows IA 32-bit local build finished on sc11137317

#### ifarmTAG "End Core Build" "" "1425685789"

#### RETAG "End Core Build" "FAILED" "03/06/15 15:49:49"