sudo dpkg -i oracle-xe_10.2.0.1-1.0_i386.deb
after installing packages need type
-e
'/etc/init.d/oracle-xe configure'
type 8080
1521 and SYSTEM or SYS and password
and
'/etc/init.d/oracle-xe start'
as root user to configure database

APEX 2.0 on UBUNTU 8.04 with database space of 4 GbytesLINUX