Why doesn´t it work?

I have a real bad problem with Mail4me. I have tried to install the progr=
am=20
into nokia 6310i and sony-ericsson p800. I can install the program into n=
okia=20
phone, but it doesn=B4t work. I get an error msg "Application not support=
ed".=20
And the program doesn=B4t even install in sony-ericsson. In sony-ericsson=
 I get=20
an error message during installation "something about that java version n=
ot=20
supported or something like that". With sun wtk emulators (both sony-eric=
sson=20
and nokia) the program works very good.=20
Someone pls tell what=B4s wrong...