Can Org warn me if I create a time conflict?

[David Rogers]

It's currently possible for me to create two meeting times, one from 8:00-10:00 
tomorrow and the other from 9:00-11:00 tomorrow. 

When both are mentioned in the same sentence, as above, it's easy to recognize 
that the two meetings are probably incompatible. But org-mode allows agenda 
items to be created at different times and in different files; it's possible to 
create Meeting #1 far in advance, have enough time to forget that Meeting #1 
exists, and then create Meeting #2 covering the same period of time. (Compare 
this with the wall calendar made of paper, where if I try to add Meeting #2 
I'll be forced to write it in the same physical space, and therefore 
automatically be alerted before making the error.)

Is there any method to get org-mode to alert me (by an error message, or a red 
mark in the agenda, or whatever) that I've created a conflict - specifically, a 
method that doesn't involve me having to remember to perform any type of 
conflict-checking myself? If I could remember to do things like conflict 
checks, I wouldn't really need org-agenda anyway. :-)

I realize that it's likely some situations *do* require timed events to happen 
concurrently - but I don't believe that they're the usual case for an 
individual. Having an "ignore conflict" or "accept anyway" type of option would 
make sense to me for such situations. 

-- 
Thanks
David