Are you having any trouble with battery life?

I can put in fresh batteries one day, take a few fotos and the next time I go to use the batteries are depleted. Happens with rechargeable and non-rechargeable batteries.

Any hints to battery life?

Can't comment on the Pentax, but the one time I thru in some std AA 's in my Fuji E900 while my rechargables were charging, those std AA's didn't last long....A day! However, my rechargables work well!

Also, does your camera have an option to discharge the batteries prior to recharging? This will help length of charge.

I'm totally amazed on how fast my digital chews up the NiCad batteries. However, your situation seems a little
too fast to me. Most cameras turn themselves off or go into a sleep mode when not active. You might want to make sure you are turning your camera fully off when not in uses.

Make sure you have decent batteries. For my flash I use the industrial grade duracells which I pick up cheaply at Batteries Plus. Costco for basic Duracells.

The wive's tale about keeping them in the frig is just that. If you're out in the cold and they fail, take them out, put them in your pocket, and replace when warm again. Anybody using a digital should always carry spares. Some digitals work better on their dedicated nicads or similar products while others do better on standard batteries.

If you keep having problems you might need to send it in for an inspection. There might be some function not turning it self off thus draining your battery.