First of all, I'd like to say that FCKeditor is the finest online editor I've had the pleasure of working with - excellent work. The thing is, as far as I see there's no support for RTL-LTR toggle in FCKeditor.
I run a nuke-based Hebrew site (http://www.hevra.org.il) and would like very much to work FCKeditor, but as Hebrew ir written right-to-left, editing Hebrew text with FCKeditor is a pain in the neck (so is the case in arrabic and a few other RTL languages).
In case this is can be easily accomplished in FCKeditor, a default configuration setting (RTL or LTR as default) would also come in very handy.
I'd be happy to translate FCKeditor to Hebrew if you're interested, and would like to hear your opinion on my feature request.