The milestone release is the first stable version of the 5.x development branch, said FreeBSD developer Scott Long in the release announcement.
The main features of FreeBSD 5.3 include improved performance on multi-processor systems and the introduction of a software layer which allows the native use of Windows network drivers.
Improved symmetric multiprocessor (SMP) performance has been achieved by making the network and socket subsystems multi-threaded and re-entrant, according to the release. The native use of Windows NDIS network drivers has been made possible by the introduction of a binary compatibility interface for the i386 platform.
FreeBSD developers have also made updates to the development and graphical environments in 5.3. It includes version 2.6.2 of the GNOME desktop, version 3.3.0 of the KDE desktop and version 3.4.2 of the GNU Compiler Collection (GCC).
Long told ZDNet UK last week that there has been considerable interest in FreeBSD 5.3 due to the need for stability in the FreeBSD 5.x development branch.
"Many people have been waiting for FreeBSD 5 to be stable," said Long. "There has definitely been an increase in interest in the last few months -- we have noticed an increase in emails and bug reports."
FreeBSD 5.3 was initially due in the beginning of October, but was put back due to a problem with network stability when the system was put under a heavy load, according to Long. This problem has now been fixed and Long is encouraging people to download the software.
"We have tested it quite a bit and it's running well under load," said Long. "We encourage everyone to give it a try."
The next version of FreeBSD, due in February or March next year, will not contain major new features, said Long. "5.4 will mostly be a refine of the 5.3 release -- we will be working on fixing bugs and improving performance," he said.
More details on the 5.3 release can be found here.