Build : JDK 5.0 u1 b07 (1.5.0_01 b07)
Build location : /net/mizu.sfbay/usr/re/jdk1.5.0_01/bundles/solaris-sparc/b07-2004-12-02/
Bundles : jdk-1_5_0_01-solaris-sparc.tar.Z & jdk-1_5_0_01-solaris-sparcv9.tar.Z (Pkg)
Platform : Solaris 10 (sparc) b72

Description :
Before installation, the system did not have 1.5.0 JDK and no /usr/jdk/instances/jdk1.5.0 directory.
Installation of 5.0u1 b07 packages (32 and 64bit) completes successfully.

Upon uninstall, /usr/jdk/instances/jdk1.5.0 directory exists. It has following folders.
/usr/jdk/instances/jdk1.5.0/jre
/usr/jdk/instances/jdk1.5.0/jre/bin
/usr/jdk/instances/jdk1.5.0/jre/lib
/usr/jdk/instances/jdk1.5.0/jre/lib/ext

All the above folders are empty.

NOTE: This problem was reproduced in 2 out of 3 machines.