Here's the HOW-TO from Oracle telling how to install it. The error you received really isn't an error, but only part of what you need to do to get it running.
10g Official Install
I am having problems starting Oracle Database 10g Express Edition on Fedora. Here is what I did in order to start it:
[root@x1-6-00-c0-9f-bb-ba-57 ~]# /etc/init.d/oracle-xe start
[root@x1-6-00-c0-9f-bb-ba-57 ~]# xhost +
access control disabled, clients can connect from any host
Not sure what I am doing wrong here. Help would be appreciated. Thanks...