This article was originally published in php|architect in April 2009 and I published it mostly as it appeared in the magazine shy of the odd formatting to fit the blog format better and updated a few year references.
Just remember, this article was written a while ago and any references to PHP 4 reflect that, take it with a pinch of salt :-)
In my last blog post, I went on a little rant about version naming standards and how that standard has helped PEAR, and other projects, to deal with their version naming and what users and developers can expect from the naming rules (e.g. seeing Foo- 0.5.0beta5 = A backwards compatibility break could happen) and so on. A version naming standard is a positive thing, but now I’m going to focus on something that is both a positive and at the same time a negative side effect of the version naming standard we keep in PEAR, something people have both praised and condemned PEAR for. Yes people, it is backwards compatibility.