Postgres 9.0.4 / Installation problem - Ubuntu 11.04 - 64bits

Hi,

I am trying to install Postgres 9.0.4 in my Ubuntu 11.04 64bits.
I've downloaded "postgresql-9.0.4-1-linux-x64.bin", and I run it as "gksudo ./postgresql-9.0.4-1-linux-x64.bin".
A graphic Installation goes fine until almost 100%, when it shows a message "Creating service user account". Since this installation message appears in the installation window, it gets like frozen, no progress. (I left the installation process running for much hours, but it did not finished)

While the installation process was with no progress, I checked what "postgres" processes were running, and I got this one:

/opt/PostgreSQL/9.0/installer/server/createuser.sh postgres /opt/PostgreSQL/9.0

I tryed to run "createuser.sh" by myself to see why it stopped. When I ran createuser.sh, the script prompted me the password for the user postgres. I do not know if this is the problem, but I believe that the installation did not finished because the installation was waiting for the password.

Does anyone have some idea to solve this problem?

ps: I do not know if this information is useful, but my computer is using LDAP for user authentication.

Thanks in advance.