Event information need a better customization

I noticed some issue on how events are rendered.

For instance, I've created and event that has a start and day, but not start and end time.

This is rendered as On 07/04/2012 from 00:00 to 31/05/2012 00:000<br />

Now, since my website is in Italian and I'm working on an Italian po file, I could play a little bit with the string "On %s from %s to %s
", but anyway I'll have to put all three place holders or I would get even worse results.

As a side note, HTML in gettext strings is not a good practice.

I think that the plugin itself should understand when an even is without a beginning/end time (all day event).

Some examples:

* A one week workshop that start April the 7th and ends on April 14th. It doesn't have a specific end date. then I could add additional "sub events" for specific classes.
* A concert that start at 21.00 but that hasn't a defined end time

All these cases as many that right now I can't think, need to be handled by the plugin itself, I think.

Right now I have to hide the event's details and rewrite them on the content: redundant and avoidable.