How do I setup an extremely simple font-lock mode?

[Matt Noel]

I want to setup a very simple mode for colorizing a log file.  All I 
need to do is highlight any lines with the string ERROR on them.  I've 
tried reading the documentation for font-lock but it's not clear how to 
do this.

Could someone point me to a simple example, or send one?

Thanks.

Matt Noel                               mgn000@yahoo.com
                                or      mgn000@mac.com