Can Dart keep Wifi from "sleeping", if so, how?

I've setup a wifi-only voip/sip thing that's worked pretty good so far, except that it seems the wifi shuts off if the phone sleeps a long time. I'm not sure how long it sleeps before wifi shuts off, but if it only sleeps around 5 minutes, my phone's green light is still lit up.

I've checked back with a few different tutorials for my GV/GT/SipDroid/PBXes WiFi Voip and have their recommended settings in SipDroid. I set the laptop that runs the the network to not shut off the network when the laptop goes to sleep, so I'm thinking something in Dart isn't configged properly?D

I had my old cell call my Dart after it had been asleep a few hours to see if maybe a call forced it awake, but it went straight to voice-mail without ringing. I sure hope it's a mistake on my end, otherwise I'm kind of bummed that all that studying was only for intermittent Voip? But as a smartphone newbie, I'm hoping it's my fault, and can be corrected

 

I've found WiFi Power Manager to be helpful - it doesn't allow for continuous wifi connection, but it does help extend how long my phone's wifi stays awake.