yes, there was a p3 450mhz coppermine, but only mobiles with socket nano bga2.
this one is the only real p3 mobile 450mhz in the database
http://www.hwbot.org/community/submission/809927_dewa_oc_cpu_z_pentium_3_mobile_450mhz_coppermine_451.03_mhz
the other ones are obviously p3 coppermine 600mhz.
440bx chipset doesn't support 133mhz offically, so because of multi 4.5 cpu-z thinks it's a p3 450.