Dell Inspiron 1525 Error code 3600:0749 Invalid AC adapter detected

Hi!
I've been following some of the power adapter conversations with Bill. I personally have an inspiron 1525 (MyDell) with no problems, and I have just recieved a clients computer of the same make and model. The clients dell inspiron 1525 (CDell) has the "plugged in not charging" fault. To date here is what I have tried;

a new battery from dell, x,
flahing with current BIOS, x,
my charger in client machine x,
my battery in client machine x,
client battery in my machine, Good,
client adapter in my machine, Good,
new battery in my machine, Good,
new battery in client machine, x,
uninstalled microsoft battery adapter, then reinstalled, x,
every possible combination of battery add remove with adapter add remove and restart, x,
neither adapter recognized in client machine BIOS,
client adapter not recognized in my machine BIOS,
reversed 2 pin plug into adapter, x,
reinstalled power managment drivers in client machine, x,

Now recieving Error code 3600:0749 Invalid AC adapter detected, with the client adapter in the client computer. Client computer 14 months old and client is pretty angry after finding out that he is one more victim in a long line. Please help me restore this guys faith in Dell (I'm a fan - hence why I have my own). I'd be realyy happy to provide service tags etc.

Thanking all in a blaze of optimism!