I'm new to hibernate, have only make a small app that reads and writes to one small table, so only got the basics.

But now I need to write a pieces of code that watches a database, and if a "special" string is inserted in to the database the app needs to react. The database is a select only syslog_ng database.
That means that sometimes there will be ALOT of inserts(syslog_ng does this ;-) ), and i need to keep up with this, so that I don't loss any of the entrys. I can not afford to loss a entry or read the same twice, and when the "special" string comes in I need to react with in seconds.

Is this something Hibernate can do and can do great?

I think this would be using an overkill aproach to the problem. If you need a single query only looking for a word it has no sense for me to use Object Relation Mapping.
Rather, you should be using JDBC directly.