If by 'utf8 chars' you mean Perl strings, try this: 
$text =~ s/ \\u ( \p{Hex}{4} ) / chr hex $1 /gex;

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In reply to Re: ASCII encoded unicode strings on web, such as \u00F3 by Anonymous Monk
in thread ASCII encoded unicode strings on web, such as \u00F3 by igoryonya

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