How do you fix cracked stucco on outside of house

[donnatahoe]

I had a sliding glass door installed a few years ago. Now there are many cracks leading from the door over the walls. I am in the process of painting and want to fix this before I paint. Additionally, someone told me that stucco is porous and that you can not "retrofit" windows (or sliders) because they will always leak and that is my problem with the cracks in the stucco... is this true?
Thanks for your help,

[marksr]

I've painted a lot of stucco but I've not installed many windows. Basically the new window would be flashed and caulked as needed and then where the stucco was removed to facilate the old window removal and new installed - is restucco'ed. The stucco [when dry] is then caulked to the window.

While bigger cracks may need to be filled with mortar/stucco, I usually caulk the minor ones.