Install Oracle Database 10 Gb in Red Hat Enterprise Linux 5.4

Install Quick Installation Guide 10g Release 2 (10.2) for Linux x86.

Problems encountered during installation:

Start Oracle Universal Installer/tmp/OraInstall from the following address. please wait... [oracle @ nj15 database] $ Exception in thread "main" java. lang. internalError: Can't connect to X11 window server using 'localhost: 100' as the value of the DISPLAY variable.
At sun. awt. X11GraphicsEnvironment. initDisplay (Native Method)
At sun. awt. X11GraphicsEnvironment. <clinit> (Unknown Source)
At java. lang. Class. forName0 (Native Method)
At java. lang. Class. forName (Unknown Source)
At java. awt. GraphicsEnvironment. getLocalGraphicsEnvironment (Unknown Source)
At java. awt. Window. init (Unknown Source)
At java. awt. Window. <init> (Unknown Source)
At java. awt. Frame. <init> (Unknown Source)
At oracle. ewt. popup. PopupFrame. <init> (Unknown Source)
At oracle. ewt. lwAWT. BufferedFrame. <init> (Unknown Source)
At oracle. sysman. oio. oioc. OiocOneClickInstaller. <init> (OiocOneClickInstaller. java: 37
At oracle. sysman. oio. oioc. OiocOneClickInstaller. main (OiocOneClickInstaller. java: 2091)

# Vi/etc/inittab
Change id: 5: initdefault: to id: 3: initdefault
# Reboot
Log On with boot in text mode
# Startx
$ Export DISPLAY = "xxx. XXXXX: 0.0"