OK, I've been able to create a very simple test case, which I would really appreciate someone else trying out & reporting back. You can get it from here:
http://cshandley.co.uk/temp/MOS_DT_crash_test.lha

Reboot (please!), then unpack it to RAM, open the Shell, then run it by typing:
MOS_DT_crash_test

For me it reports the following:
Quote:

This indicates that the byte at offset 27 has been corrupted by DisposeDTObject(). The source code is included, but you cam view it here too:
http://cshandley.co.uk/temp/MOS_DT_crash_test.cpp

(I should note that I don't expect the test to ALWAYS see the corruption, because it relies upon MorphOS's TLSF memory system to allocate the memory block directly after whatever the datatype allocated (or perhaps in the same location as a something it allocated & then freed). This seems likely to happen, at least after a reboot when there is little external fragmentation.)

[ Edited by ChrisH 20.10.2011 - 23:02 ]