C-x 5 f problem

[Silviu Minut]

I use emacs 20.7-34 on a RedHat 7.1 machine. I have my emacs aliased as

alias emacs='emacs -bg black -fg white -cr red -ms white -fn 10x20
-geometry 80x25'

Notice the geometry is 80x25. When I do

emacs myfile &

the window has geometry 80x25 as I wanted. However, if within this
window I do

C-x 5 f my_new_file

emacs opens a new window with geometry 80x40, which expands beyond the
borders of the screen.

There was no such behavior in RedHat 7.0, so I'm wondering if this is a
bug. Or is it some variable that I need to set to control the geometry
of subsequent windows? If it's a bug, is there a fix?

I apologize if this problem has been addressed before.