Nishant,
> "php home/xxxx/public_html/cron.php" is this correct Syntax for Cron ?
Recommended format for crontab is:
0 0 * * * cd /full/path/to/xpayments ; /path/to/php/bin -f /full/path/to/xpayments/cron.php
0 0 * * * - to run script every day
cd /full/path/to/xpayments - to change dir to X-Payment folder on your server
/path/to/php/bin - path to PHP 5.3 CLI binary on your server
-f - to execute /full/path/to/xpayments/cron.php script
I'll update our knowledge base right away, too.
UPD:
http://help.x-cart.com/index.php?title=X-Payments:Installation#Running_cron.php_script