Hi,
take a look into the file .history in the folder "$specroot/Install-Tools/". Example:
9.3.0.0.304 02/14/2014 15:17
9.3.0.1.82 03/11/2014 09:05
The Hotfix is the 4rth number, in this case I have installed Spectrum 9.3 with HotFix 1.
Regards,
Christoph