The Gnu Project has released version 3.4.3 of GCC,
the GNU Compiler Collection.
GCC contains frontends for C, C++, Objective C, Chill, Fortran, Ada, and Java as well as libraries for these languages.
GCC is a clean room implementation of Java that doesn't use any Sun code,
so it doesn't always exactly match Sun release versions, but this is roughly at the Java 1.4 level with some omissions. 3.4.3 is a bug fix release, mostly focusing on C++ isssues but it does fix one "GCJ segmentation fault while compiling GL4Java .class files."
Etienne Gagnon has released version 1.1.7 of SableVM, a Java bytecode interpreter (that is, a virtual machine) written in portable C. "SableVM requires an ANSI/ISO C compiler (but preferably GCC) and a POSIX platform. It requires a strong memory model (sequential consistency) on multiprocessor systems." SableVM is available for GNU/Linux. Solaris, Mac OS X, and FreeBSD. Version 1.1.7 allows users to add to the bootclasspath, improves error messages for bootstrap problems, adds a new generational garbage collector and fixes a number of bugs. SableVM is published under the GNU Lesser General Public License (LGPL).