Found several other cases (all of those segfaulting due to dependency between itcl- and oo-subsystems).

Ultimate fix is provided now in branch [/timeline?r=bug-1dc2d851eb|bug-1dc2d851eb].
Merged into trunk, because this all is to classify as grave resp. critical.<br/>
Additionally, I cannot really work on another issue (affecting memory/references subsystems) as long as the whole system is basically unstable.