Some organizations require open source. Others forbid its use. Those willing to consider both can compare AOLserver versions in a few technical dimensions. AOLserver 2.3 has matured for more than two years. Version 3.0 is officially a beta release.
Some vendors use beta as a euphemism for flaky or untested.
Don't think this about the AOLserver development team, though. Its engineering is quite conservative, and plenty of Web sites already have version 3.0 beta 3 in production. Platform compatibility for both versions is broad. Binary versions for a variety of common Unix platforms are available, and while Red Hat 6.0 with glibc 2.1 is the only Linux officially supported, AOLserver works properly with essentially all distributions. AOLserver's 3.0 release is unusual for having removed several features from its earlier 2.3 manifestation.