Cannot modify SafeBuffer in place

Upgraded from rails 3.0.7.rc1 to 3.0.8 today and ran into a problem when
rendering haml:

TypeError in Pages#home
Cannot modify SafeBuffer in place

Full Trace:

activesupport (3.0.8)
lib/active_support/core_ext/string/output_safety.rb:122:in gsub!' haml (3.1.1) lib/haml/compiler.rb:382:inblock in build_attributes’
haml (3.1.1) lib/haml/compiler.rb:358:in each' haml (3.1.1) lib/haml/compiler.rb:358:incollect’
haml (3.1.1) lib/haml/compiler.rb:358:in build_attributes' haml (3.1.1) lib/haml/compiler.rb:407:inprerender_tag’
haml (3.1.1) lib/haml/compiler.rb:119:in compile_tag' haml (3.1.1) lib/haml/compiler.rb:447:incompile’
haml (3.1.1) lib/haml/compiler.rb:446:in `block (2 levels) in compile

Only way I can avoid the error is if I remove everything from
application.haml below %body

devth wrote in post #1003840:

haml (3.1.1) lib/haml/compiler.rb:382:in `block in build_attributes’

HAML 3.1.2 fixed that:
http://groups.google.com/group/haml/browse_thread/thread/208f9e9fb0ec9906

Hope that helps!
François