Here's a solution... 
my $tab = 8;

while ( <DATA> ) {
  chomp;
  my $fixed = join '', map { $_ . ' 'x($tab-length) } split /\t/;
  print "$fixed\n";
}

__DATA__
hello    57    *45    78
there    *57    93    *83
dude    78    23    *45

[download]
Enjoy! Update: This code will not work of a field is longer than 8 chars, but the following will:

ps. I don't think any of the other responses take that for account either, but if I'm wrong, I'll retract that. 

my $fixed = join '', map { $_ . ' 'x(((int(length()/$tab)+1)*$tab)-len
+gth) } split /\t/;

[download]
--
Casey

In reply to Re: Conditionally converting tabs to spaces by cwest
in thread Conditionally converting tabs to spaces by Anonymous Monk

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