Hi, I've reworked the Tcl/Tk checking code in setupext.py (see attached patch). It is now possible to build matplotlib with Tk support without requiring a running X server. This is useful for doing autobuilds (e.g. as done by Debian) and for building a package on one machine to be installed and used on another. This seems to be an old issue... (see matplotlib-devel, "building matplotlib without X-server connection," 11 Nov 2004) The patch also fixes a potential hang, which happens when I try to build the latest matplotlib on Debian Etch with Python 2.4, on a system with libtk8.4-dev installed but no running X server. The build should have continued without TkAgg support, but it hangs. The hang occurs because the Tcl/Tk checking code calls Tkinter.Tk() multiple times, which is not a good idea. In fact, just running the following snippet hangs the interpreter in this scenario: import Tkinter tk = Tkinter.Tk() tk = Tkinter.Tk() The patch applies to setupext.py in revision r3975. I checked it with matplotlib r4064, using Python 2.4 on Debian Etch, and Python 2.5 on Mac OS X 10.4.10. Could someone please check it with Python 2.3 and on Windows? Regards, Ludwig