Salaries of short term players hired and released mid-season

[mac]

My punter gets injured in week 9 so I hire a replacement at the minimum salary. He plays in weeks 10 and 11 but then my original punter is recovered so I cut the replacement. But the replacement gets paid for playing 11 weeks rather than 2. The program ignores the fact that he has only just been signed and instead assumes he has been on the roster since week 1.

Is this an accurate reflection of real life?
I thought NFL players were paid by the week (other than bonuses) and marginal players are often being picked up for a single game to fill in for injuries.
This has happened to me a few times in FOF 2004 and in FOF2007. It is particularly annoying when you are low on cap money but have enough to pay for a minimum player for the remainder of a season but not for the whole season.
Perhaps when signing players in mid season the default should be per week therefore instead of 340k a season it should be 20k a week so hiring someone for two weeks would cost 40k regardless of when it happened.

Apologies if this is an old issue or if this actually reflects real life.
Despite my whining I love this game.