Hope Platonides, Jeroen or someone else very familiar with Mediawiki's core can answer this and provide a quick explanation or recommendation.
I know it is recommended when setting custom namespaces to use standards, like FOO or FOO_TALK. What are the pitfalls of FOO1.0 or FOO1.1 as a namespace. Is it better to use an alias, such as FOO11 would be aliased to FOO1.1? I know the problems with Apache rewrite and have dealt with them when some of my users tried to create page titles with the ? and * characters. What if any problems could be expected with the .(period) character.
Thanks Tom