I am the author of the plug-in Cimy User Extra Fields.
Most probably soon there will be a change in WordPress where wp_print_styles() will be called in the login/registration page, see the ticket:
http://core.trac.wordpress.org/attachme ... 7916.patch
If you try to apply the patch your css files will be present in the login and registration page too messing up with the background and other layout items.
I tend to consider that this is a bug in your theme, please be so kind to investigate it.
Suffusion Version: 3.8.3
WP: 3.2.1 + patch above