I'm pleased to announce the release of ProGuard 5.2. This update fixes a number of bugs reported since the previous release. It also extends the support for converting obfuscated stack traces back to their unobfuscated counterparts. ProGuard writes out an extended mapping file, which ReTrace can then use to "de-obfuscate" stack traces from the obfuscated code. ProGuard, ReTrace, and the format of the mapping file are backward and even forward compatible, but if you want to get the most out of it: go ahead and upgrade!
You can find the release notes and download links on ProGuard's download page. The release is compatible with previous releases, so upgrading your build process can be as simple as replacing the ProGuard jar.
You can also find the binary artifacts on Maven Central.