Build numbers and release dates for Exchange Server
I've spent a little bit of time this week trying to guess a Exchange Version and SP (I know that SM tell you that! ) but looking for it in a Dump file without access to SM it's harder, so I've remember a very useful KB article, that I used in the past and by coincidence a colleague of mine has recently send it to me, so here it is the table and Kb link hope that this will help you all in the future (thanks Tude!)
http://support.microsoft.com/default.aspx?scid=kb;EN-US;158530
