MOSS Version Numbers

How to check SharePoint Version level running:

1) Goto IIS, select the MOSS website
2) Right click and select Properties
3) Select HTTP Headers tab and you should be able to see a custom HTTP Header called "MicrosoftSharePointTeamServices" with a version number by its side.

MOSS 2007 or WSS 3.0 Hotfix (KB953484 - KB953473 - KB953471) 12.0.0.6317.500
MOSS 2007 or WSS 3.0 Hotfix (KB953138 - KB953137) 12.0.0.6316.500
MOSS 2007 or WSS 3.0 Hotfix (KB952704) 12.0.0.6315.500
MOSS 2007 or WSS 3.0 post-SP1 hotfix (KB952294) 12.0.0.6314.500 [In SSP admin you will get a new Search Administration option, which brings the Search Server features to MOSS.]MOSS 2007 or WSS 3.0 post-SP1 hotfix (KB948945) 12.0.0.6303
MOSS 2007 or WSS 3.0 post-SP1 hotfix (KB941274) 12.0.0.6301
MOSS 2007 or WSS 3.0 post-SP1 hotfix (KB941422) 12.0.0.6300
MOSS 2007 or WSS 3.0 SP1 12.0.0.6219
MOSS 2007 or WSS 3.0 October public update 12.0.0.6039
MOSS 2007 or WSS 3.0 August 24, 2007 hotfix package 12.0.0.6036
MOSS 2007 or WSS 3.0 RTM 12.0.0.4518
MOSS 2007 or WSS 3.0 Beta 2 TR: 12.0.0.4407
MOSS 2007 or WSS 3.0 Beta 2: 12.0.0.4017

Credit: Boby Habib