Startup error message

Error message at startup:
"HazelHelper.app" is an application downloaded from the internet. Are you sure you want to open it?
Safari downloaded this file on May 2, 2012 from www.noodlesoft.com.
How do I stop this behavior?
"HazelHelper.app" is an application downloaded from the internet. Are you sure you want to open it?
Safari downloaded this file on May 2, 2012 from www.noodlesoft.com.
How do I stop this behavior?