The problem with JavaME is that even the standardized profiles do not match on every phone (besides possible extra package differences to look after on i.e. mobilezoo). Same things may work on one phone but not on the other which needs other tricks. There are even specialized companies that do nothing but converting a source base to 100 different phone models. Why do you think you have to select your model with Jamba or Gameloft? It's not just the resolution!

I like JavaME and the programming with it but the more you try to achieve the more problems occur with a way to napless specification. First and foremost of course the problems of porting between phones. But its not just between vendors but also inside a company. For example I one programmed on the SE K800 phone emulator as I own that special cellphone. On the emulator everything worked fine, on my phone it didn't even start. I do not remember what the problem was (it was fixable after all), but I still remember that flaw that kept me sleepless.