Sorry it's taken me so long to respond on this one. I've been away for a while. I think that it might be possible to count the number of <blockquote> tags; however, other codes also use the <blockquote> and it may give a false reading. What you really need is some sort of iterative counter, though how that would be implemented is a bit beyond me.
I haven't had a chance to upgrade to 6.1 yet. Hopefully I will have some time this evening to at least get my testboard up and running. I'll see what I can do and post any updates in the Beta forum.