I deleted system app dialer from iphone 3gs ios 5.1.1 through ifunbox?

I guess it was named facetime.app can anybody provide the that app… M unable to make calls.

A Predictive Dialer includes a list of telephone numbers and connects answered dials to people making calls, often called agents. Predictive dialers use statistical algorithms to minimize the amount of time agents spend waiting between conversations, while minimizing the occurrence of someone answering when no agent is available. [1]
When dialing a number at once, there are two sources of delay. First, only a fraction of the dials are answered. For example, if 1 out of 3 dials are answered, a predictive dialer could call three lines each time an agent is available. Second, even dials that are answered take some time before being picked up.