I recently got the WIP300. Although I know it is a rather old phone, I liked it because of it's size. I got it to work with my Sipgate.de account, but I have to reboot the phone every day at least once to stay connected. In the display it shows my router name and my phone number, but I can't make or receive calls. Once restarted this problem is solved, but pops up some hours later...
I think you need to upgrade the firmware of the WIP phone. Download the firmware from the linksys website and upgrade the firmware of your Phone. Once the firmware is upgraded then you need to reset the phone and re-configure all the settings on it again.
