Dia

Dia is an advanced tool that allows you to create different kinds of diagrams. It includes tools for drawing UML, flow, network and other diagrams. It is possible to add support for new shapes, by writing XML files using SVG for drawing. Diagrams can be loaded and saved in their own XML format (gzipped by default to save space), and also exported to a range of formats including EPS, SVG, XFig, WMF and PNG, or printed (including those involving multiple pages).

Multi-language interface!