I tried to make a portlet with JSF and Spring but i have experienced some difficulties.

I didn't succeed to integrate JSF and Spring into Jboss Portal, so i gave up
and use Portlet taglib instead of JSF. it works well for what i want to do.

Anyone can tell me the diference between Portlet taglib and JSF, can i do everithing with portlet taglib?

Why Portlet taglib exists? what is the purpose of it knowing that
other technologies exists

i'm a bit confused.