When you call another object in Oz (or do anything else, for that matter), the program happily waits until processing is completed, and will happily wait indefinately. This is a bit of a problem in a language where many bugs cause hangs.
While there's not much MOZ can do to stop you from causing a hang in your own code, there are timeouts on calls to other objects, so that another object being hung doesn't permanently hose your own code.
The default timeout is 500 microseconds (i.e. half a second). To
alter this timeout, add the feature activeObjectWaitTime to
the method call with the feature holding a positive integer
representing the timeout you want, or nil to wait forever.
Note that the method making the call may also be under a timeout, so waiting 3000ms when the callee will timeout in 500ms is rather pointless.
Verb calss have the rather grotesque timeout of 6 minutes.
start methods never timeout.