Haven't played with the charger for that model, but the charger that came with my Blade 400 was pretty cheesy....
I'm guessing that the one you got was something similar, so with that in mind I'd suggest you get yourself a real Li-Po capable charger considering how much trouble one can get into with Li-Po batteries. If you're going to keep playing with them a new safer/better charger would seem to be in order?
Right now, FMA has the little CellPro 4S on sale for $49.95 and you'll need the E-flite adapter which runs about $10.00. It'll balance charge your batteries and check for bad cells while it's doing it, puts out up to 4 amps and is the only one anywhere near that price range which does active balance vs. passive. i.e. it will bring up the low cells as it charges, rather than discharging the high cells before it starts charging like most balancing chargers, so it's faster.
JMHO, YMMV...
http://www.fmadirect.com/products.htm?cat=45&nid=4