How to invoke dbca from UNIX server console command line

I attempted to invoke dbca to create a Oracle 10GR2 db for RMAN on a HP-UX

I exported ORACLE_SID = rcat and invoked dbca and received errors on 3 occassions:

1)  I performed dbca and recieved an error message that DISPLAY was not set

From /etc/hosts file on server:

ww.xx.y.zz serv_console  # Local console port

2) I performed

a) export DISPLAY=ww.xx.y.zz:0.0

b)  dbca and it encountered an error.

3)  I attempted setting

a) export DISPLAY=localhost:0.0

b)  dbca and it never came back.