Have you contacted Panasonic for advice on extending the cable?? I would not want to cut the lead unless it's a last resort but i do find it strange that the tv lead isn't long enough, i presume your sockets are some distance from the tv then which would mean you could run a simple extension lead to the socket and connect the tv to that although it will look a little messy.
If i remember correctly the GT30 i had did have a strange connection into the tv but i think it's just a safety feature to stop the lead being pulled out, i'm sure there will be a standard connection underneath it if it's the same connection but i would seek advice and contact Panasonic.
Apart from running an extension lead or cutting the power lead i can't think of any other way around it, i have the same issue and killed two birds with one stone and bought a tacima mains conditioner lead that extended to my kit rack and i plug into that with the bonus of decent power supply now getting to my kit. I've got plans to mount that to the wall and box it in so i can isolate all the power cables from all my other cables when i get the time and motivation.