It seems ikegami (and my unstated suspicion) were correct. Bleadperl now dies:

perl-5.9.4-build$ ./perl test-CDS.pl
Too late for "-CDS" option at test-CDS.pl line 1.
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I thought the error looked familiar, so I tried it with "-T", but I see that one is now updated to:

perl-5.9.4-build$ ./perl test-T.pl
"-T" is on the #! line, it must also be used on the command line at te
+st-CDS.pl line 1.
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(With perl5.6.0 and perl5.005_03, I get the familiar:)

old-solaris-machine$ perl5.6.0 test-T.pl
Too late for "-T" option at test.pl line 1.
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So, it seems it was a bug, but it's been fixed in the 5.9 line.