OEM batteries and laptop BIOS

Archived from groups: comp.sys.laptops (More info?)

I bought an OEM battery to replace the original one in my IBM ThinkPad
X20. The old battery charges fine but is old and doesn't give much
charge time anymore. The new battery won't charge all the way. The
charger's blinking light never goes steady, and I only get about 1:30
hours when I should get 3:00 hours or more. It was this way out of the
box, and I've only had the new battery for a few days.

The vendor's support person says that I need a BIOS update because the
original BIOS doesn't recognize OEM batteries. Does this sound
plausible or does it sound like the vendor is trying to delay issuing
an RMA?