You love "5", don't you? :)

I'd probably filter all non-alphanumerics, and then split on any string of letters.

while (<DATA>) {
    chomp;
    tr/A-Za-z0-9//cd;
    my ($number, $extension, $overflow) = split /[A-Za-z]+/;
    if ($overflow) {
        warn "Don't know how to handle number '$_'.\n";
        next;
    }
    print "Number: $number";
    print ", extension: $extension" if defined $extension and length $
+extension;
    print "\n";
}
__DATA__
(555) 555-5555
555.555.5555
555-555-5555
(555)555.5555
(555) 555-5555 x.555
555.555.5555 Ext. 555
555-555-5555 ext.555

[download]

U28geW91IGNhbiBhbGwgcm90MTMgY
W5kIHBhY2soKS4gQnV0IGRvIHlvdS
ByZWNvZ25pc2UgQmFzZTY0IHdoZW4
geW91IHNlZSBpdD8gIC0tIEp1ZXJk

In reply to Re: Simple Regex by Juerd
in thread Simple Regex by sevrin

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