increasing minecraft's allocated RAM

I'm using the launcher kingagnostic has on the hacks page. i'm trying to use the .bat thing but it has two errors: cannot create java virtual machine. and fatal error.

.bat thing

@EcHo off
javaw -Xmx1500M -Xms1024M -jar "location of launcher"

works fine with official launcher, but not with the hacked ones. help pls!

1.Its not KingAgnostic's Client, its AnjoCaido's Client.

Head over to crucial.com to buy RAM