If you assume that a line can only end with a period (.) or a double-quote ("), then the following seems to give the desired output: 
#!/usr/bin/perl -w
use strict;

undef $/;

my $text = <DATA>;

$text =~ s/([^."])\n/$1 /g;

print "$text";

__DATA__
this is a
wrapped line.
"This is a wrapped
quote."
this first line is fine.
so is this one.

[download]
Prints: 
this is a wrapped line.
"This is a wrapped quote."
this first line is fine.
so is this one.

[download]
Cheers,
Darren :)

In reply to Re: replacement of newlines by McDarren
in thread replacement of newlines by neodymium

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