You may have better luck changing the code to: 
my $ham = "spam\tspam\tspam\t\tyam\tclam";

my @jam = ($ham =~ (m/^[^\t]+\t[^\t]+\t([^\t]+)(\t\t)([^\t]+)\t[^\t]+$
+/));

print join("\n", '**', @jam, '**', '');

[download]
prints: 
**
spam

yam
**

[download]

In reply to Re: How to capture quantified repeats? by umasuresh
in thread How to capture quantified repeats? by whatever

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