I could reproduce this bug in 1.4.2, but is fixed in 1.5 (KDE 3.5).
You can 'fix' it by choosing another font.

SVN commit 475425 by okellogg:

Give user the possibility to manually adjust the bounding box of widgets,
i.e. merge class ResizableWidget into UMLWidget.
BUG:114892


 M  +1 -1      ChangeLog  
 M  +0 -1      umbrello/Makefile.am  
 M  +10 -10    umbrello/activitywidget.cpp  
 M  +2 -2      umbrello/activitywidget.h  
 M  +27 -22    umbrello/actorwidget.cpp  
 M  +2 -2      umbrello/actorwidget.h  
 M  +37 -45    umbrello/artifactwidget.cpp  
 M  +8 -7      umbrello/artifactwidget.h  
 M  +2 -2      umbrello/boxwidget.cpp  
 M  +2 -2      umbrello/boxwidget.h  
 M  +34 -36    umbrello/classifierwidget.cpp  
 M  +3 -9      umbrello/classifierwidget.h  
 M  +22 -25    umbrello/componentwidget.cpp  
 M  +6 -5      umbrello/componentwidget.h  
 M  +6 -7      umbrello/datatypewidget.cpp  
 M  +4 -4      umbrello/datatypewidget.h  
 M  +13 -14    umbrello/entitywidget.cpp  
 M  +4 -3      umbrello/entitywidget.h  
 M  +14 -15    umbrello/enumwidget.cpp  
 M  +5 -5      umbrello/enumwidget.h  
 M  +10 -10    umbrello/floatingtext.cpp  
 M  +6 -5      umbrello/floatingtext.h  
 M  +22 -11    umbrello/forkjoinwidget.cpp  
 M  +11 -11    umbrello/forkjoinwidget.h  
 M  +9 -15     umbrello/messagewidget.cpp  
 M  +2 -2      umbrello/messagewidget.h  
 M  +15 -24    umbrello/nodewidget.cpp  
 M  +4 -13     umbrello/nodewidget.h  
 M  +12 -15    umbrello/notewidget.cpp  
 M  +4 -4      umbrello/notewidget.h  
 M  +15 -17    umbrello/objectwidget.cpp  
 M  +2 -2      umbrello/objectwidget.h  
 M  +13 -22    umbrello/packagewidget.cpp  
 M  +8 -16     umbrello/packagewidget.h  
 D             umbrello/resizablewidget.cpp  
 D             umbrello/resizablewidget.h  
 M  +16 -15    umbrello/statewidget.cpp  
 M  +2 -2      umbrello/statewidget.h  
 M  +1 -1      umbrello/umlview.cpp  
 M  +100 -37   umbrello/umlwidget.cpp  
 M  +19 -3     umbrello/umlwidget.h  
 M  +12 -12    umbrello/usecasewidget.cpp  
 M  +2 -2      umbrello/usecasewidget.h  

On Saturday 29 October 2005 10:38, Oliver Kellogg wrote:
> ------- Additional Comments From okellogg users sourceforge net  2005-10-29
> 10:38 ------- SVN commit 475425 by okellogg:
>
> Give user the possibility to manually adjust the bounding box of widgets,
> i.e. merge class ResizableWidget into UMLWidget.
> BUG:114892


I'm not sure this will improve usability. Since the size of a widget can be 
calculated entirely based on the contents, user intervention will make the 
auto-resizing system more annoying/counter productive. For example, when is a 
manually set size overridden by umbrello ? when a new item is added/removed ? 
never ? Some widgets may be resizable, but all by default ? I really liked 
the way umbrello handled connection points of associations automatically. 
Compare with *nightmare* dia, moving an item on a diagram means reconnecting 
all associations to the proper side of the widget. I vote for tuning the 
auto-layout functions, instead of investing in things a user doesn't want to 
do in the first place.

Peter

> [...] For example, when is a 
> manually set size overridden by umbrello ? when a new item is added/removed ?

The automatically computed size continues to be used
on addition/removal as well as for the minimum possible
size that is attainable by manual resizing.

> [...] I really liked
> the way umbrello handled connection points of associations automatically.

That feature remains intact even in the presence of manual resizing.