Mod/Hack to trick iPhone about default phone app?
I'm definitely a noob, and I'm fully aware.
I just got my first iPhone. I am not going to be using a carrier for phone calls. Unfortunately the previous owner of the phone updated to 4.2.1 and was not a jailbreaker, therefore no SHSH blobs to revert to 4.1. So I am jailbroken, but on the tethered Redsnow jailbreak for 4.2.1. My plan is to get a wifi hotspot from the newish company called Clear so that I have constant wifi connection, and then use the VoIP App "Line2" for calling and texting. Because of this, I have no need for the official Apple Phone App.
My question is:
Would there be any way to trick the iPhone into thinking that Line2 is the default phone app as opposed to the official Apple Phone App that would typically be used if I had a carrier? It may be too complex of a mod for my limited dev/hack/code skills, but I thought I would ask if anyone has ever done or tried to do anything similar to this.
Any help or advice would be greatly appreciated!!!