Unable to change password circle character size

I have openSUSE 11.4 (i586) installed with KDE version 4.6.5 “release 7”. My graphics card driver is Nvidia-computer G02 version 304.43-20.1.
I would like to know if there is a way to change the font size of the password circles. The font sizes of the login name and desktop environment are fine (I changed them from kde personal settings) but the password font size i.e circle size is large. I followed some posts in the forum and added the following in /etc/sysconfig
“kdm4” in Display manager
I have also added “ServerArgsLocal=-nolisten tcp -dpi 96” under [X-:*-Core] of the kdmrc file located in /usr/share/kde4/config/kdm. Nothing seem to change the size of the password circle character. Please help !