Using the 1g2 version of the exceptions package,
filed into 2.4b image, I had a problem.
When I changed the critical: method in
Semaphore to 
aBlock valueEnsuring: [self signal]
The semaphore is sent a message like
#DoItWith
Which it does not understand.

Can anybody shed some light on,
or reproduce this problem?

Here is the relevant part of the walkback:
---------------------------------------------------------------------
Sat Jun 12 20:20:37 1999

Current byte code: 210
Primitive index: 85
Stack dump follows:

25523032 Semaphore>doesNotUnderstand:
25522720 PostOffice>protected:
25521828 PostOffice>incoming:from:
25519868 Object>trigger:withAll:
25519420 Object>trigger:
25465912 PostOffice class>testBasicAdd
25465756 PostOffice>DoIt

The other thing I've noticed about
Semaphores when you inspect them
is that sometimes the inspector
is inspecting a process, not the 
semaphore itself. Has anybody else
seen this?

Peter