I tryed using the Yii extension for Eclipse in Eclipse Kepler Standard (version: Kepler SR2) with PDT 3.2.0.201306051924.
After installing, the behaviour of Eclipse changes duplicating all entries in the Auto Complete Proposals relate to variables and project classes.
Tryed unchecking autocomplete features of the extension but the problem persists.
Also the behaviour of text prediction becomes unstable, showing options after entering characters as ; or {}
Only solution was to uninstall the extensión and behaviour went back to normal.