In a regular expression, "\t" is a tab character, and I'm not sure what "\m" is, if anything.

use Test::More 'tests' => 2;

ok( 'sef.mlxhelp.com' =~ /(\.mlxhelp)\.com/,
    q{'sef.mlxhelp.com' matches} );
ok( 'www.mlxhelp.com' =~ /(\.mlxhelp)\.com/,
    q{'www.mlxhelp.com' matches} );
[download]

Note that these will always put ".mlxhelp" in $1 when they match because the capturing parentheses are around that literal string.

what I am after here is capturing what url they are requesting and if it matches then supplying a login page for that particular account, since I don't want to do this 115 times, I was hoping to find a way to match it without iterating over all these possibles, I am not sure if module test:: will run on perl 5.6.1 and am very hesitant to add anything to the perl install as this is a production box. excellent point about the \t I forgot about that. I can't figure out how to get it to even echo what the url is if I type it manually can someone please tell me what I am doing wrong. there may be more than one way to do it, but I would like to find the one that works the good news is I already have discovered several that don't

 sub transform
  {
      if (!$Session->{'isAuthenticated'}) 
      { 
      #Following statement checks if site is www prefix if so it check
+s tempo or mlxhelp and uses appropriate stylesheet
      #for each this only checks www. prefix need another to check the
+ rest of the potential matches
   
    
       
      if ($Request->ServerVariables("SERVER_NAME")->item()=~/(\w+)\.co
+m/) 
       {  
          $domain = $1;
         #$Response->write("This is the domain");
          if ($1 eq 'tempohelp')
          {
          my $trns= $Server->MapPath("Transforms/tpLogin.xsl");
          return $trns;
          }
          if ($1 eq 'mlxhelp')
          {
          $Response->write("This is the domain $1");
          my $trns=$Server->MapPath("Transforms/pLogin.xsl");
          return $trns;
          }
       
       }
       #closes wwww prefix check..
    if (!(substr($Request->ServerVariables("SERVER_NAME")->item(),0,3)
+ eq "www") && !(substr($Request->ServerVariables("SERVER_NAME")->item
+(),0,3) eq "mlx") && !(lc($Request->ServerVariables("SERVER_NAME")->i
+tem()) eq "localhost"))
      {
     $Request->ServerVariables("SERVER_NAME")->item() =~ /([\w]*)\./;
      $str .= ".$1.";
      $Response->write("this is $str");
     }
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At this point, I think perhaps it's time to insert some debugging statements and see what's really going on in there.

if (!$Session->{'isAuthenticated'})
{
    $Response->write( 'session is authenticated' );
    my $server_name = $Request->ServerVariables("SERVER_NAME")->item()
+;
    $Response->write( "server name is '$server_name'" );

# ... etc ...
}
[download]

Get yourself a list of server names that you'll want to match and then take them into a separate small test program to make sure you can get what you want out of them.

my $server_name = 'www.example.com';
my ( $prefix, $domain )
    = ( $server_name =~ m{ \A (\w+) \. (\w+) \. com }xms );
print "prefix: '$prefix'\n";
print "domain: '$domain'\n";
[download]

Also, my use of Test::More was just for demonstration. It's normally used for testing, not for anything else.