The Joomla! team has recently published Joomla! 1.5 RC3 and is constantly developing Joomla! 1.5 with their limited ressources. In the past we (the VirtueMart Development Team) have tried to make VirtueMart compatible to Joomla! 1.5 with more or less success. Although Joomla! 1.5 provides a "Legacy Plugin" that emulates Joomla! 1.0 functions, it must be said that this doesn't really turn Joomla! 1.5 into a Joomla! 1.0. Some of the legacy functions work differently compared to the original functions in Joomla! 1.0.
After all we have decided to stop our compatibility efforts for VirtueMart 1.0.x and Joomla! 1.5 and just make the upcoming VirtueMart 1.1 compatible to J! 1.5 instead.
So from now on the VirtueMart 1.0.x series is officially not compatible to Joomla! 1.5 (even not in Legacy mode).
We apologise for any inconvenience this might cause, but currently it's not possible for us to concentrate on development for VirtueMart 1.0.x and VirtueMart 1.1.
When will VirtueMart 1.1 be stable? We will soon publish another beta release, which will bring you the latest state of development for testing (Nightly Builds are available). We need you for making VirtueMart better! Bug Reports are just one part of the game. Our Teams need people. If you feel, you can help us, please apply for a job in one of the new teams.