It doesn't look like it. Exegesis 4 does have a lexical constant declaration, 
my $n is constant = 11;

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but my copy of Perl 5.10 doesn't like it, 
Bareword found where operator expected at scoped_const.pl line 5, near
+ "$n is"
        (Missing operator before is?)

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In reply to Re: 5.10: Are scoped constants possible? by quester
in thread 5.10: Are scoped constants possible? by BrowserUk

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