Hmm, try to download the latest update (which was last week) and make sure that the footnote option is enabled. The plugin is set to "opt-out" so it means that you have to enable it per-post for it to be active. You can change this in the plugin settings.

I have the latest Update from your page.

I have footnote enabled but I always get the Illegal Tag.

I've tried in three different blogs in two different servers with the same results.

I must be missing something...

meh.. this is wierd...
This may be a stupid question (because I'm out of ideas, really) but... how do you type your footnotes? Try just using the examples in the help file (which I assume, you did already...I think).

Could you try it on a 1.10.x build?

Edit: The problem is, 1.9.3 doesn't support a certain plugin event (UnfilterItemContents/FilterItemContents) which the plugin requires. I'll see what I can do about it.

Edit#2: Updated the plugin to version to support version 1.9.x by using bbcode instead, check the footnote site.

I've tried the plugin in 1.8.5 and 1.9.3, I don't have a 1.10 blog yet until it is declared stable because all blogs I have are production blogs.

What do you mean with BBcode, you mean to turn on that plugin and try yours with it? How would the BBCode be?

What I mean is, get the latest one (check that the version is 0.2.x), go to the plugin settings and check "Use Alternate Syntax".

After doing that, instead of using the X/HTML syntax, the one that uses angle brackets (i.e. <footnote note="foo">bar</footnote>), you can use the BBcode-like syntax (i.e. [footnote note="foo"]bar[/footnote]). It's not really BBcode per se, but it's uses the same form as BBcodes

OK, I'll try it and will inform you of the results.

OK, this time it worked with version 0.2. It worked in a version 1.9.2, now I'll try in 1.8.5 and 1.9.3

Thank you!