Hi, I'm curious if anybody knows if there is some kind of wall charger available to charge the N810 batteries "BP-4L" type. I'm wanting to get a few spare (genuine) BP-4Ls for trips and such, but I don't want to have to charge them through the N810.

So far the closest thing I've found is a bunch somebody is selling on eBay.com for about $5.00 (includes a (no doubt) knock off BP-4L battery), here's an example:

http://buyeng.ebay.com.hk/buying/hk/...-E61i-E90-E90i (if that dies, simply search ebay for "BP-4L charger")

Has anybody tried this? I would just toss the battery, but how safe is the charger? Will it harm the genuine batteries? Will it damage the N810? Will it shorten the batteries life or capacity?

This is pretty much exactly what I'm looking for but I am fairly concerned about it being a Hong Kong seller since I imagine it's not a Nokia authorized accessory. Would using this invalidate the warranty?

Thanks so much for your help.