[carpeperdiem]

I searched for this in the future...

IN 4.5.4, edit file:

/common_files/modules/One_Page_Checkout/payment_methods.tpl

find:

{$payment.payment_details}
{if $payment.processor eq "cc_mbookers_wlt.php"}

replace with:

{* BEGIN var in payment details mod *}
{* {$payment.payment_details} *}
{eval var=$payment.payment_details assign="paydtls"}
{$paydtls}
{* END var in payment details mod *}        
{if $payment.processor eq "cc_mbookers_wlt.php"}

(looks like $payment_methods[payment].payment_details became $payment.payment_details sometime between 4.1 and 4.5)

Hope this helps someone (possibly me?) in the future.