After several months of delays, Debian developers have released Debian 4.0, code-named "Etch."

Aside from the systems it powers directly, Debian forms the basis for dozens of other operating systems, including MEPIS, Knoppix, Ubuntu and Xandros. Public-sector Linux projects such as that of the city of Munich are tailoring custom Linux systems based on Debian.

The software was under development for 21 months, according to the project. Etch supports 11 processor architectures and includes the GNOME, KDE and Xfce desktop environments and cryptographic software, and is compatible with version 3.1 of the Linux Standard Base (LSB), a project that seeks to keep different versions of Linux closely compatible.

Etch introduces support for encrypted partitions, and a package management system called Secure APT, which verifies package integrity and allows for smaller package updates.

The OS includes recent versions of such open source mainstays as PostgreSQL, MySQL, Apache, Samba, Python, Perl and Asterisk, and is based on Linux kernel version 2.6.18.

Debian, one of the most highly regarded Linux distributions, was originally planned for release on 4 December. A funding project called Dunc-Tank was created to help meet the deadline by funding two release managers - Andreas Barth and Steve Langasek - to work full time fixing bugs.

The deadline came and went, causing frustration for Debian developers, many of whom disagree with the basic idea of setting a release deadline. In a January developer poll on release date expectations, nearly half refused to specify a date, saying the distribution should be released when it is ready.

Many developers also disagreed with the Dunc-Tank project, causing some to slow down their work.

Long release delays have been a persistent problem with Debian, one factor that led to the creation of the Debian-based Ubuntu project. Ubuntu has a commercially oriented sponsor in the form of Canonical, founded by South African IT billionaire Mark Shuttleworth, and has stuck to a more frequent release schedule.

In February, Canonical and Linspire announced a technology partnership that will see Linspire and Freespire move to a Ubuntu base, while Ubuntu users will gain access to Linspire's software delivery technology, called CNR. Linspire was previously based on Debian.

The companies specifically noted that Linspire would "benefit from Ubuntu's fast-moving development cycles."