how do you deal with heavy power cords?

Hospital Grade recepticles should have enough clamping power to hold onto the prongs on the plug. For the IEC end I would wrap a piece of electrical tape around the perimeter of the IEC and then plug it into the unit. At least worth a try if you havn't already.

I have the same problem.
This might work for the wall outlet, though I haven't tried it:

http://www.buypowergear.com/detail.aspx?ID=5165

As for the IEC end, everything I've seen requires holes to screw into, like these:

http://www.qualtekusa.com/catalog/na_power/retainer.html

If you find something better, let us know.

i have jps 'aluminatas and they,too,are very heavy...what i did was to make a 1" thick wood block with cut outs for the outlets...i have a quad outlet...and take velcro tape and tape the wood block to the outer limits of the wall outlet with the velcro....then plug the pcs' through the holes into the outlets..the 1" wood thickness holds the plugs in nicely and does not allow them to lever out...hope this helps

Only thing that I have found that works for me is to cut out a piece of wood (but any other materials would probably work too, even found around the house) and prop up the cable. I use blueTack then to prevent this piece from moving. Since I am not moving around equipment, as I am able to pull my complete rack out, this is the only thing that has worked for me.

For the wall outlet, I have not experienced this problem. But you can also bend out the prongs a little bit to get a tighter fit to help it hold in better.