Module can not be installed and saved

Hello, It seems weird. I have been drupal user for many years. I never faced such situation. When I try to install and save this module, it keeps showing this:
Payment for Drupal Commerce 7.x-1.4 Allows Drupal Commerce orders to be paid using Payment.
Requires: Commerce_payment (missing), Payment (enabled), Entity API (enabled)

But I am unable to find this Commerce_Payment module which is required and which it shows here as missing. Even more weird is the point that : I downloaded this module considering it as Commerce_Payment module, but after installing it shows the name Payment for Drupal Commerce (as given in its dor info file) and requires Commerce_Payment module to be installed first. Please help .. where can I find this seemingly mythical Commerce_payment module?