Hi RHCA,

you may want to edit your "sudoers" file. How to do that:

login as "root" in a console window by typing

$ su -

at the prompt.

Then you can edit (with any text-editor) the text-file "/etc/sudoers" by changing 1 line (by commenting out the line beginning with "knoppix" by a leading "#" - without using the quotation marks) and adding a new line for user "RHCA" - that's YOU - expressing the rights of "RHCA" for executing privileged commands by "sudo".
_______________________
# /etc/sudoers
...
...
# knoppix ALL=NOPASSWD: ALL
RHCA ALL=NOPASSWD: ALL
_______________________

Hth.

-nohype