JDK on Linux

Hi Guru's

We want to install Solman 4.0 and ECC 6.0 on RHEL5(redhat linux enterprise) and maxdb 7.6

Please suggest us which jdk that we need to go for(Sun or IBM).

Please do let us know about the versions like jdk 1.4.2_xx etc.

Your help would be more appreciable

Thanks,