BOUML
Bouml : a free uml toolbox running under unix/linux/solaris and windows to specify and generate code in c++, java, php, python and idl
http://bouml.free.fr/
Rational
Rational
http://www-306.ibm.com/software/rational/
UML-template
UML-template
http://www.gnome.org/projects/dia/
Umlgraph
Umlgraph
http://www.spinellis.gr/sw/umlgraph/