distributor_admin error

Hi,
When i try to configure publisher, distributor, subscriber on the same remote server, i am getting the following error:
SQL Server Enterprise Manager could not configure '90.168.XX.XXX' as the distributor for '90.168.xx.xxx'
Error: 18483: could not connect to server 'different name' beacuse 'distributor_admin' isn ot defined as a remote login at the server
I changed the MSSQLSERVER and the SQL Server Agent and a dependant file to run froma domain account, i gave that domain account all the privileges on the database and the master database aswell. but i keep getting the error.
Also why is the error showing diffetent server name than the '90.168...' name?
Will i have problems later if i donot set up alias names rather than ip address. If so, how can i set up alias names for SQL Server's
I am quite new to all this, any detailed answer could really help.
thanks
stummalaGot that fixed by re registering the server name to the result of @.@.SERVERNAME