use-case to sequence diagram

[gpc]

Hi,
I have a use case diagram and want a use case element to link to a sequence diagram located elsewhere in the 'tree'.
I can do this by;
1. move the sequence diagram to be contained by the use case element.
2. right-click on use case element and select advanced->composite element.
3. move sequence diagram back to its original location.

This works, but; should it? (i.e. will this functionality suddenly disappear in a bug fix?) and is there a better / easier way to achieve the same result.
Thanks.

[thomaskilian]

This is kind-of EAUI standard. It is not documented but works in that way (also for other elements). Frankly speaking: undocumented features may vanish, but for EA it seems to be quite unlikely