For quite some time I used to produce Windows builds for both Wammu and Gammu using cross compiling on Linux. But this has proven to produce some errors and needed my time to maintain the cross compilation environment. I've decided to stop producing Windows binaries and I don't expect to get back to that anytime soon.
This is actually no news for Wammu, where I've removed Windows builds some about two years ago as they proven to be too broken for normal usage, but for Gammu it's new as previous release had Windows builds. I've lost the cross compilation environment due to hard drive failure and restoring it is simply too much of work and still will not allow me to build complete release (I've not managed to build Python modules properly).
So if anybody is interested in Windows binaries, he needs to produce them on Windows. I can help with fixing code or existing setup scripts (they probably need adjustments as they were tweaked for cross compiling), but somebody has to setup the environment with all dependencies and test the build on Windows.