Powerbook G4 Power Adapter

Okay, here's the deal:

Accidentally ripped the smaller cable out of the power adapter for my 17" Powerbook G4. This was a 65 Watt adapter. I have an extra 60 watt mag safe adapter, so I spliced the smaller wire off the 65 watt adapter, cut the cable off the 60 watt mag safe and spliced it as well, and joined the two. Now I have a 60 watt mag-safe power adapter with a round-end 65 watt power adapter. I plugged it into my 17" powerbook g4, and low and behold the light turned on, and it provided power to the powerbook. It wasn't until a little while longer that I noticed the powerbook battery wouldn't charge, it would just stay at the percentage (if the percent was lower than 99). Simply, I didn't see that the charger was charging the powerbook.

I guess my question is that, is it possible that the 60 watt mag-safe charger is just charging the laptop much slower? Why is it not charging the laptop? Could there be any damage to the laptop/battery by using a 60 watt power adapter rather than a 65 watt? Thanks

The 60W and the 65W power adapters output different voltage so while while I'm not sure if their will be any long term damage from using a lower wattage adapter with your PowerBook, the lower voltage output from the 60W will not be enough to charge the battery.

Apple has the 65W power adapter for iBook/PowerBooks for $79US:
Extra Portable Power Adapter - 65W (for iBook & PowerBook) - Apple Store (U.S.)

65W iBook/PowerBook Power Adapter:
Input Voltage Range: AC 100V - 240V
Output Voltage: DC 24V Power
Output Current: 2.65A

60W MagSafe Power Adapter:
Input Voltage Range: AC 100V - 240V
Output Voltage: DC 16.5V Power
Output Current: 3.65A

You can get third-party ones that are perfectly good for much less.