Kaffe thread scheduling bug

[William Chesters]

Following up on the reasons why IFC doesn't work under Kaffe/BISS AWT,
I came up with the test program listed below.

Results:

java YieldTest n n
java YieldTest n y
java YieldTest y n
java YieldTest y y
    all three threads run; once a second it prints "a/b/c"

kaffe YieldTest n n
    all three threads run; once a second it prints "a/b/c"

kaffe YieldTest n y
kaffe YieldTest y n
kaffe YieldTest y y
    as soon as a thread yields, it stops; prints "a/b/c"
    once, then nothing