HELP!! WHERE IS THE PHP CODE LOCATED for Authorize.Net???

[txnational]

Using an Authorized.Net Emulator which is verifying addresses but NOT the CVV2 (# on the back of the card). eProcessing Network simply tells me to edit the code. I'm a beginner at all this PHP stuff!?!?!? So I need your help...I'm trying to locate the x_type and "no transaction" in the php code and delete the x_type and/or x_transtype and set "no transaction" to ON. I made the php change in the authorizenet.php file and it still is allowing INVALID CCV2 credit cards to be processed. So I called again..... Eprocessing Network techs said in Magento there is an x_type, x_transtype, and possibly a "no transaction type" option which needs to be turned ON. Kinda the same story.... One question... WHERE IS THE PHP CODE LOCATED that controls Authorize.Net payments(NOT Direct Post)?????

A big THANK YOU in advanced....

[eMagicOne]

Hi, it should be here:

app/code/core/Mage/Authorizenet

[txnational]

Thnaks for the response eMagicOne,

Not sure what lines in the Authorizenet.php code control verfication of the Card Verification Number.

Here is the Card Verification Number html below when checking out. I'm trying to locate the Magento php script that controls this since it is processing ANY 3 digit CVV2 code that gets input to this field. It should decline the transaction if the 3 digit number DOES NOT match the number on the back of the credit card being used. Since I'm using an Authorize.Net Emulator rather than a regular Authorize.Net account Magento basically ignores verification of the Card Verification Number. Any insight into what exact line or lines control this process would be quite helpful.

<input type="text" title="Card Verification Number" class="input-text cvv required-entry validate-cc-cvn" id="authorizenet_cc_cid" name="payment[cc_cid]" value="" autocomplete="off">