This is a very strange issue. So far I found the following...

Some ZC orders come through and state credit card payment method with no card number, type etc...

No Authorize.net transaction info either declined or approved. Just nothing.

No debug info in cache for AIM also just not there. So it doesn't even attempt to contact Authorize.net

Majority of orders work fine only a small number has this happen and it appears random.

I am using 1.3.8 with super orders module. Here is my curltest.php info

CURL Test Page
This page is intended for testing CURL behaviour. You should be accessing this page via CURLTEST.PHP running on YOUR server.


You submitted the following fields and data:
Array
(
[field1] => This is a test
[statuskey] => ready
)
Data validation
Good
Other Info

Array
(
[url] => "http://www.zen-cart.com/testcurl.php"
[content_type] => text/html
[http_code] => 200
[header_size] => 139
[request_size] => 174
[filetime] => -1
[ssl_verify_result] => 0
[redirect_count] => 0
[total_time] => 0.123527
[namelookup_time] => 0.115204
[connect_time] => 0.116012
[pretransfer_time] => 0.116035
[size_upload] => 0
[size_download] => 2140
[speed_download] => 17324
[speed_upload] => 0
[download_content_length] => 0
[upload_content_length] => 0
[starttransfer_time] => 0.123507
[redirect_time] => 0
)


Any ideas what this could be. I think it may be card or user specific as one user it does it everytime they order. I am still investigating that though.