The specified size exceeds the maximum representable size

If you run this:

java -Xms4096m Bla

and you get this:

Invalid initial heap size: -Xms4096m
The specified size exceeds the maximum representable size

it simply means that you are using a 32bit JVM instead of a 64bit JVM.

check "java -d64"

java -d64 -version Error: This Java instance does not support a 64-bit JVM. Please install the desired version.