It looks like they sent you PC2700 RAM. Your CPU is 133 MHz external FSB, so it's not gonna let the RAM run any faster than PC2100. No problems, it just appears that they sent you PC2700 instead of 2100.
Of course, it could be the program simply not detecting the RAM properly. I'd go with them sending you faster RAM than you bought, though...or you accidently ordering 2700 without realizing it.
-Lasereth