Mixing Unicode and Latin-1 class texts
Since ECMA allows class texts to be written as either sequences of CHARACTER_8 of CHARACTER_32 (which although not properly specified yet, we can assume means Latin-1 or Unicode), there arises the question of to what extent the two can be mixed.
It is clear that fully unrestricted mixing is not possible. For instance, if a class written in Unicode has a routine named 了, then this routine cannot be called from a class written in Latin-1 (unless it is passed as an agent).
I would suggest that a suitable rule is that all classes within a cluster must either be all CHARACTER_8 or all CHARACTER_32. Furthermore, no class in a CHARACTER_8 cluster may depend upon a class from a CHARACTER_32 cluster.
This rule suggests a requirement for the ACE/XACE/ECF file formats to be able to specifying the character size used for writing class texts within a cluster (or library too, perhaps).