error message when credit card module disabled

i installed payflo pro to use as my all-in-1 paypal, credit card, etc. and am having some problems. if i turn off the credit card module and try to pay through pp, i get a page of:

Warning: strstr() [function.strstr]: Empty delimiter. in /var/www/domains/store.sweetbeautyspa.com/docs/includes/modules/payment/payflowpro.php on line 337

Warning: Cannot modify header information - headers already sent by (output started at /var/www/domains/store.sweetbeautyspa.com/docs/includes/modules/payment/payflowpro.php:337) in /var/www/domains/store.sweetbeautyspa.com/docs/includes/functions/functions_general.php on line 41

when i keep the credit card module ON, the option to pay by credit card shows up twice in my checkout. and if i try using the second credit card option i get a Result code: 127:

help? thanks

Whats there at line 337 in /var/www/domains/store.sweetbeautyspa.com/docs/includes/modules/payment/payflowpro.php

The block of code around line 337 is:

      // collapse array into string for command-line submission
      $parmList = '';
      foreach($transaction as $key=>$value) {
        if ($key == 'NAME' || strstr('&', $value) || strstr('=', $value)) {
          $parmList .= '&' .$key . '[' . strlen($value) . ']' . '='.$value;
        } else {
          $parmList .= '&' .$key . '='.$value;
        }
      }

it's failing on the strstr() call, but I don't know what's in $value at that point.
Incidentally: when I phoned PayPal about this, the tech said that he's never seen a successful integration from Zen to PayPal, that he has fielded lots of calls with this same error. There's got to be someone who's figured it out.

its becuase not all value of $value are getting submitted
Again there should be something like
if(empty(!$value))
inside the for loop...just a suggestion