This is not a framework request but a request about the website part that hosts the class references: http://www.yiiframework.com/doc/api/ (yes I used bettor's words ![:)]()
Sometimes you want to link to a direct Anchor in a class reference, like http://www.yiiframework.com/doc/api/1.1/CHtml#checkBoxList-detail
If you write it like above, it works, but if you remove the "www" or the version number ("1.1" here), you lose the anchor and are redirected to an anchor-less link, like http://www.yiiframework.com/doc/api/1.1/CHtml
So here are 2 examples that do not work as expected:

Sometimes you want to link to a direct Anchor in a class reference, like http://www.yiiframework.com/doc/api/1.1/CHtml#checkBoxList-detail
If you write it like above, it works, but if you remove the "www" or the version number ("1.1" here), you lose the anchor and are redirected to an anchor-less link, like http://www.yiiframework.com/doc/api/1.1/CHtml
So here are 2 examples that do not work as expected: