I am sorry if this has been covered before but in 1.7.2 the event is named "beforeclose".  In 1.8pre it is named "beforeClose" (camelCase).

Two things:

First, that needs to be thoroughly documented.

Second, WTF?  This gratuitous breaking of user-code is, to my eye, really, really rookie.  ESPECIALLY considering how trivial it would be to support both, at least for a time.

**--**  Steve