It's similar, but not the same issue. The difference lies in testing with AND and +, with + it seems to fail whereas with AND it seems not to.

Seems similar to this issue:
http://www.ventismedia.com/mantis/view.php?id=6637

thought it was fixed though.

Query was exactly "rating:3.. +nightwish" without the quotes. Any query that combines a rating:<param> +anythingelsethatIhappenedtotry will generate a similar error.

Searching the entire library.

And what query did you enter? I also assume you didn't search the entire library, but current selection instead?

The quick search box at the top of the window whilst in the media library. Sorry if that wasn't clear from the subject line.

Where did you enter this search?

I've linked a screenshot of the error below. Seems pretty straightforward (missing space between the number 56 and the operator AND).

[url]http://picasaweb.google.com/lh/photo/Ia51WqiibInvab4WRowCc2_VdiYTYekXpFa7Lgg0KEM?feat=directlink[/url]

Using version 3.2.4.1304 Gold which I believe to be the latest release.