Apparently, ACL hates (or :utf-8 :default) as expanded by the #+ reader. Instead, I'm expanding to (progn :default :utf-8). Does that work better? I pushed 2.20.5 - can you test?
As for the CMUCL failure, I can't reproduce, using a CMUCL snapshot 2011-06 (20B Unicode) on x86/sse2.
—♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org