How to simulate pressing enter in html text input with Selenium?

Question

In a web interface, I've got a text field. When user enters text and accepts with enter, application performs an action.

I wanted to test the behavior with Selenium. Unfortunately, invoking 'keypress' with chr(13) insert representation of the character into the field.

Is there a way other then submitting the form? I'd like to mimic intended user interaction, without any shortcuts...