As the docs say, You have to do it: 
use 5.006_001;

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It even works with Perl 5.6.1. A bit strage ( weird? ). I don't know why they had to broke compatibily this way. 
-- 

<-- z0d -->

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In reply to Re: v-string warning in 5.8.0 by z0d
in thread v-string warning in 5.8.0 by Ferret

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