Ok I've found a MathFP that is supposed to solve the double and float absence problem.
By the way I'm new to J2ME ;)
So I've the 2 jar files into my project and the compilation is ok but when I launch my application I have this error message:
Error starting MyAppxxx58; Module 'jmfp-bin-0.99' not found.
Any clue ?
Thanks in advance