Deleting older versions of Java

Today my NIS 2011 virus scanner found and quarantined a virus called Trojan.ByteVerify.  In researching it a bit I find that I should probably delete all old versions of Java -- only keep the most recent one.  I had two programs listed for Java in Add/Remove other than the current version.  They were Java 6 update 15 and Java SE Development Kit 6 Update 15 (64-bit).  I got rid of Java 6 update 15 but got the "Publisher Unknown" message for the Development Kit:

 

Do you want to allow the following program from an unknown publisher to make changes to this computer?

 

Program Name:  C:\Windows\Installer\23c59.msi

Publisher:  Unknown

File Origin:  Hard drive on this computer

Program Location:  Update

                                    1.6.0.150

                                    Sun Microsystems, Inc.

                                    English (United States)

                                    C:\Windows\Installer\23c59.msi

 

Does anyone know if this is okay to go ahead and uninstall?