Browser detecting if Acrobat is installed on client machine

[masonf]

I need to know if it's possible to detect whether Acrobat is installed on the client machine so I can display a message to the user when he/she visits our website. We have a lot of documentation in PDF format and some of our users don't have the appropriate viewer installed.

I looked at the response.servervariables but there was no mention of "PDF" in the mime types, even though the machine I am using has it installed.