Digital Signatures

I recently did an update of Java and I noticed in my browser (IE7) 2 sun objects

 

ssv.dll and jp2ssv.dll  

both of these rae located in the bin folder of C:\Program Files\Java

both were downloaded the same day and time. However, one  (ssv.dll) has a digiatl sig from Sun Microsystems and the other does not.

Isn't that odd that two dll items from the same provider at the same time and only 1 is digiatlly signed?