<p>I know this can be done in IE by creating an ActiveX object, but how do I do it in FF. The navigator.plugins['Adobe Acrobat'] object lets me know if it's installed or not, but it doesn't contain the version number. Any ideas?</p>

```
navigator.plugins[n].name
```
where
```
n
```
is the index of the Acrobat plugin is supposed have the version number in it. Unfortunately, starting with Adobe Reader 8, they changed the name to
```
"Adobe PDF Plug-In for Firefox and Netscape"
```
, with no version information. So, if this is the name you've detected at least Reader 8, but can't tell versions 8 from 9.
Also, make sure you take into account that Macs don't need Acrobat Reader to render PDF files. (I booted my Windows partition just to test this.)