Ubuntu login screen

[Reinier Millo Sanchez]

I'm using ubuntu 10.10. I vae found several themes for the login screen, but I don't know how can change the default theme. I have find in internet but, only can change the background, but not the whole screen. Somebody know how do it??? Regards
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Reinier Millo Sánchez
Ciencias de la Computación
Universidad Central de las Villas
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                ...                 Siempre hay
              (o -)                 un ojo que
     ooO--(_)--Ooo-         te ve.
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Universidad Central "Marta Abreu" de Las Villas. http://www.uclv.edu.cu