make/pkgdefs/SUNWj3dvx/Makefile contains this snippet:

PKGFILES = jre/bin/sparcv9/javac ...
bin/sparcv9/extcheck bin/sparcv9/jdb
PKGDBGFILES =

The extra backslash at the end of the "jdb" line is considered
a continuation character, which means that it swallows up the
following line. It's as if it were written:

PKGFILES = jre/bin/sparcv9/javac ...
bin/sparcv9/extcheck bin/sparcv9/jdb PKGDBGFILES =

which is obviously not what's intended.

This might not be causing any actual harm right now -- just some build
warnings -- but could least to maintenance problems.