Is the problem in the pre-compiled module Scalar::Util?! That came with both Linux distributions (Ubuntu 7.10 and Fedora 7).

Basically the ident function only call the Scalar::Util::refaddr, and ..

perl -e 'use Scalar::Util; $ref = qr//; print "$ref\n"; print Scalar::
+Util::refaddr($ref)."\n";'
(?-xism:)
0
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And after recompilation and installation of the module (same version, 1.19)

perl -e 'use Scalar::Util; $ref = qr//; print "$ref\n"; print Scalar::
+Util::refaddr($ref)."\n";'
(?-xism:)
135576940
[download]

And the tests for the Class::Std::Utils module

Class-Std-Utils-v0.0.3# prove t/ident.t 
t/ident......ok    
All tests successful.
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