Small UML Diagram Tool

I need a small tool that helps me drawing UML notations for classes,
squence diagrams etc.
No roundtrip engineering, just a simple little pen/paper replacement
for annotations, in fact i don't want to use my Viso program or some
other tools because they insists of stupid parameter dialogs whenever i
add for example a method name, or hundert other things.

I tried to install Dia for Windows but it fails with an relocation bug
in libiconv during startup.