HTML input time, step attribute to set timestep by (say) x minutes?

Question

I have a time input, basically just:

Time:  

http://jsfiddle.net/X8E9N/

According to

Answer 1

Yes. You can specify step attribute in seconds.

However, Opera, iOS Safari, and Google Chrome don't reject non-aligned user input. A user can specify 11:59 to such time field. Then, Opera and Google Chrome show a validation error message when he tries to submit the form.