iAntivirus Definition Update

I just install iAntivirus on June 4th and I don't understand why it is not updating virus definition.

 

I checked the Scan Preferences and it is indicated below:

Virus definition date:  5/2/12  (This is over 30 days ago..  Is this normal?)

Number of virus signatures:  36,995 (Only 37K virus signatures? )

 

Please someone let me know about how to update "iAntivirus" definition.

 

Also, can I install "iAtivirus" and "Sophos Home Free Antivirus" program same time?

 

Thank you,